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5) #include "head.wmi" TITLE="Tor Project: FAQ" CHARSET="UTF-8"
6) <div id="content" class="clearfix">
7)   <div id="breadcrumbs">

8)     <a href="<page index>">Home &raquo; </a>

9)     <a href="<page docs/documentation>">Documentation &raquo; </a>
10)     <a href="<page docs/faq>">FAQ</a>
11)   </div>
12)   <div id="maincol">
13)     <!-- PUT CONTENT AFTER THIS TAG -->
14)     <h1>Tor FAQ</h1>

15)     <hr>

16) 

17)     <a id="general"></a>
18)     <h4 style="margin-bottom: 18px"><a class="anchor" href="#general">General questions:</a></h4>

19)     <ul>
20)     <li><a href="#WhatIsTor">What is Tor?</a></li>

21)     <li><a href="#Torisdifferent">How is Tor different from other
22) proxies?</a></li>

23)     <li><a href="#CompatibleApplications">What programs can I use with
24)     Tor?</a></li>
25)     <li><a href="#WhyCalledTor">Why is it called Tor?</a></li>
26)     <li><a href="#Backdoor">Is there a backdoor in Tor?</a></li>

27)     <li><a href="#DistributingTor">Can I distribute Tor?</a></li>

28)     <li><a href="#SupportMail">How can I get support?</a></li>

29)     <li><a href="#Forum">Is there a Tor forum?</a></li>

30)     <li><a href="#WhySlow">Why is Tor so slow?</a></li>

31)     <li><a href="#FileSharing">How can I share files anonymously through Tor?
32)     </a></li>

33)     <li><a href="#Funding">What would The Tor Project do with more
34)     funding?</a></li>

35)     <li><a href="#IsItWorking">How can I tell if Tor is working, and that my

36)     connections really are anonymized?</a></li>

37)     <li><a href="#Mobile">Can I use Tor on my phone or mobile device?</a></li>

38)     <li><a href="#OutboundPorts">Which outbound ports must be open when
39)     using Tor as a client?</a></li>

40)     <li><a href="#FTP">How do I use my browser for ftp with Tor?</a></li>

41)     <li><a href="#NoDataScrubbing">Does Tor remove personal information

42)     from the data my application sends?</a></li>

43)     <li><a href="#Metrics">How many people use Tor? How many relays or
44)     exit nodes are there?</a></li>

45)     </ul>

46) 

47)     <a id="comp-install"></a>
48)     <h4 style="margin-bottom: 18px"><a class="anchor" href="#comp-install">Compilation and Installation:</a></h4>

49) 

50)     <ul>
51)     <li><a href="#HowUninstallTor">How do I uninstall Tor?</a></li>
52)     <li><a href="#PGPSigs">What are these "sig" files on the download
53)     page?</a></li>

54)     <li><a href="#GetTor">Your website is blocked in my country. How
55)     do I download Tor?</a></li>

56)     <li><a href="#VirusFalsePositives">Why does my Tor executable appear to

57)     have a virus or spyware?</a></li>

58)     <li><a href="#tarballs">How do I open a .tar.gz or .tar.xz file?</a></li>

59)     <li><a href="#LiveCD">Is there a LiveCD or other bundle that
60) includes Tor?</a></li>

61)     </ul>

62) 

63)     <a id="tbb"></a>
64)     <h4 style="margin-bottom: 18px"><a class="anchor" href="#tbb">Tor Browser (general):</a></h4>

65)     <ul>

66) 

67)     <li><a href="#TBBFlash">Why can't I view videos on YouTube and other
68)     Flash-based sites?</a></li>

69)     <li><a href="#Ubuntu">I'm using Ubuntu, and I can't start Tor Browser.

70)     </a></li>

71)     <li><a href="#SophosOnMac">I'm using the Sophos anti-virus

72)     software on my Mac, and Tor starts but I can't browse anywhere.</a></li>

73)     <li><a href="#XPCOMError">When I start Tor Browser I get an 
74) error message: "Cannot load XPCOM".</a></li>

75)     <li><a href="#TBBOtherExtensions">Can I install other Firefox

76)     extensions? Which extensions should I avoid using?</a></li>

77)     <li><a href="#TBBJavaScriptEnabled">Why is NoScript configured to

78) allow JavaScript by default in Tor Browser?  Isn't that

79) unsafe?</a></li>

80)     <li><a href="#TBBOtherBrowser">I want to use Chrome/IE/Opera/etc
81)     with Tor.</a></li>

82)     <li><a href="#GoogleCAPTCHA">Google makes me solve a CAPTCHA or tells

83)     me I have spyware installed.</a></li>

84)     <li><a href="#ForeignLanguages">Why does Google show up in foreign

85)     languages?</a></li>

86)     <li><a href="#GmailWarning">Gmail warns me that my account may have
87)     been compromised.</a></li>

88)     <li><a href="#NeedToUseAProxy">My internet connection requires an HTTP

89)     or SOCKS Proxy</a></li>

90)     <li><a href="#TBBSocksPort">I want to
91)     run another application through Tor.</a></li>

92)     <li><a href="#CantSetProxy">What should I do if I can't set a proxy

93)     with my application?</a></li>

94)     </ul>
95) 

96)     <a id="tbb-3plus"></a>
97)     <h4 style="margin-bottom: 18px"><a class="anchor" href="#tbb-3plus">Tor Browser (3.x and later):</a></h4>

98) 
99)     <ul>

100)     <li><a href="#DisableJS">How do I disable JavaScript?</a></li>

101)     <li><a href="#VerifyDownload">How do I verify the download

102)     (sha256sums.txt)?</a></li>

103)     <li><a href="#NewIdentityClosingTabs">Why does "New Identity" close

104)     all my open tabs?</a></li>

105)     <li><a href="#ConfigureRelayOrBridge">How do I configure Tor as a relay

106)     or bridge?</a></li>
107)     <li><a href="#Timestamps">Why are the file timestamps from 2000?</a></li>

108)     <li><a href="#TBBSourceCode">Where is the source code for Tor Browser?

109)     How do I verify a build?</a></li>

110)     </ul>
111) 

112)     <a id="advanced"></a>
113)     <h4 style="margin-bottom: 18px"><a class="anchor" href="#advanced">Advanced Tor usage:</a></h4>

114) 

115)     <ul>
116)     <li><a href="#torrc">I'm supposed to "edit my torrc". What does
117)     that mean?</a></li>

118)     <li><a href="#Logs">How do I set up logging, or see Tor's

119)     logs?</a></li>

120)     <li><a href="#LogLevel">What log level should I use?</a></li>

121)     <li><a href="#DoesntWork">Tor is running, but it's not working
122)     correctly.</a></li>

123)     <li><a href="#TorCrash">My Tor keeps crashing.</a></li>

124)     <li><a href="#ChooseEntryExit">Can I control which nodes (or country)

125)     are used for entry/exit?</a></li>

126)     <li><a href="#FirewallPorts">My firewall only allows a few outgoing
127)     ports.</a></li>

128)     <li><a href="#DefaultExitPorts">Is there a list of default exit ports?</a></li>

129)     <li><a href="#WarningsAboutSOCKSandDNSInformationLeaks">I keep seeing
130)     these warnings about SOCKS and DNS information leaks. Should I

131)     worry?</a></li>

132)     <li><a href="#SocksAndDNS">How do I check if my application that uses

133)     SOCKS is leaking DNS requests?</a></li>

134)     <li><a href="#TorClientOnADifferentComputerThanMyApplications">I want to run my Tor client on a
135)     different computer than my applications.</a></li>
136)     <li><a href="#ServerClient">Can I install Tor on a central server, and
137)     have my clients connect to it?</a></li>

138)     <li><a href="#IPv6">How do I use Tor from an IPv6 only host/computer?</a></li>

139)     </ul>

140) 

141)     <a id="relay"></a>
142)     <h4 style="margin-bottom: 18px"><a class="anchor" href="#relay">Running a Tor relay:</a></h4>

143)     <ul>

144) 
145)     <li><a href="#HowDoIDecide">How do I decide if I should run a relay?
146)     </a></li>

147)     <li><a href="#MostNeededRelayType">What type of relays are most needed?</a></li>

148)     <li><a href="#WhyIsntMyRelayBeingUsedMore">Why isn't my relay being

149)     used more?</a></li>

150)     <li><a href="#IDontHaveAStaticIP">Can I run a Tor relay using a dynamic IP address?</a></li>

151)     <li><a href="#IPv6Relay">Can I use IPv6 on my relay?</a></li>

152)     <li><a href="#PortscannedMore">Why do I get portscanned more often

153)     when I run a Tor relay?</a></li>

154)     <li><a href="#HighCapacityConnection">How can I get Tor to fully

155)     make use of my high capacity connection?</a></li>

156)     <li><a href="#RelayFlexible">How stable does my relay need to
157) be?</a></li>

158)     <li><a href="#BandwidthShaping">What bandwidth shaping options are

159)     available to Tor relays?</a></li>

160)     <li><a href="#LimitTotalBandwidth">How can I limit the total amount

161)     of bandwidth used by my Tor relay?</a></li>

162)     <li><a href="#RelayWritesMoreThanItReads">Why does my relay write

163)     more bytes onto the network than it reads?</a></li>

164)     <li><a href="#Hibernation">Why can I not browse anymore after

165)     limiting bandwidth on my Tor relay?</a></li>

166)     <li><a href="#ExitPolicies">I'd run a relay, but I don't want to deal

167)     with abuse issues.</a></li>

168)     <li><a href="#PackagedTor">Should I install Tor from my package manager,

169)     or build from source?</a></li>

170)     <li><a href="#WhatIsTheBadExitFlag">What is the BadExit flag?</a></li>

171)     <li><a href="#IGotTheBadExitFlagWhyDidThatHappen">I got the BadExit flag.

172)     Why did that happen?</a></li>

173)     <li><a href="#MyRelayRecentlyGotTheGuardFlagAndTrafficDroppedByHalf">My

174)     relay recently got the Guard flag and traffic dropped by half.</a></li>

175)     <li><a href="#RelayOrBridge">Should I be a normal relay or bridge
176)     relay?</a></li>

177)     <li><a href="#UpgradeOrMove">I want to upgrade/move my relay. How do I

178)     keep the same key?</a></li>

179)     <li><a href="#OfflineED25519">How do offline ed25519 identity keys work?
180)     What do I need to know?</a></li>

181)     <li><a href="#MultipleRelays">I want to run more than one
182) relay.</a></li>

183)     <li><a href="#NTService">How do I run my Tor relay as an NT service?
184)     </a></li>

185)     <li><a href="#VirtualServer">Can I run a Tor relay from my virtual server

186)     account?</a></li>

187)     <li><a href="#WrongIP">My relay is picking the wrong IP address.</a></li>
188)     <li><a href="#BehindANAT">I'm behind a NAT/Firewall</a></li>

189)     <li><a href="#OutgoingFirewall">How should I configure the outgoing filters on my relay?</a></li>

190)     <li><a href="#RelayMemory">Why is my Tor relay using so much memory?
191)     </a></li>
192)     <li><a href="#BetterAnonymity">Do I get better anonymity if I run a relay?
193)     </a></li>

194)     <li><a href="#FacingLegalTrouble">I'm facing legal trouble. How do I

195)     prove that my server was a Tor relay at a given time?</a></li>

196)     <li><a href="#RelayDonations">Can I donate for a relay rather than
197)     run my own?</a></li>

198)     </ul>

199) 

200)     <a id="onion-services"></a>
201)     <h4 style="margin-bottom: 18px"><a class="anchor" href="#onion-services">Tor onion services:</a></h4>

202) 

203)     <ul>

204)     <li><a href="#AccessOnionServices">How do I access onion services?</a></li>
205)     <li><a href="#ProvideAnOnionService">How do I provide an onion service?</a></li>

206)     </ul>

207) 

208)     <a id="dev"></a>
209)     <h4 style="margin-bottom: 18px"><a class="anchor" href="#dev">Development:</a></h4>

210) 

211)     <ul>

212)     <li><a href="#VersionNumbers">What do these weird version numbers

213)     mean?</a></li>
214)     <li><a href="#PrivateTorNetwork">How do I set up my own private
215)     Tor network?</a></li>

216)     <li><a href="#UseTorWithJava">How can I make my Java program use the

217)     Tor network?</a></li>
218)     <li><a href="#WhatIsLibevent">What is Libevent?</a></li>

219)     <li><a href="#MyNewFeature">What do I need to do to get a new feature

220)     into Tor?</a></li>
221)     </ul>
222) 

223)     <a id="anonsec"></a>
224)     <h4 style="margin-bottom: 18px"><a class="anchor" href="#anonsec">Anonymity and Security:</a></h4>

225)     <ul>

226)     <li><a href="#WhatProtectionsDoesTorProvide">What protections does Tor

227)     provide?</a></li>

228)     <li><a href="#CanExitNodesEavesdrop">Can exit nodes eavesdrop on

229)     communications? Isn't that bad? </a></li>

230)     <li><a href="#AmITotallyAnonymous">So I'm totally anonymous if I use

231)     Tor?</a></li>

232)     <li><a href="#KeyManagement">Tell me about all the keys Tor
233) uses.</a></li>

234)     <li><a href="#EntryGuards">What are Entry Guards?</a></li>

235)     <li><a href="#ChangePaths">How often does Tor change its paths?</a></li>

236)     <li><a href="#CellSize">Tor uses hundreds of bytes for every IRC line. I

237)     can't afford that!</a></li>

238)     <li><a href="#OutboundConnections">Why does netstat show these outbound

239)     connections?</a></li>
240)     <li><a href="#PowerfulBlockers">What about powerful blocking mechanisms
241)     </a></li>

242)     <li><a href="#RemotePhysicalDeviceFingerprinting">Does Tor resist

243)     "remote physical device fingerprinting"?</a></li>

244)     <li><a href="#IsTorLikeAVPN">Is Tor like a VPN?</a></li>

245)     <li><a href="#Proxychains">Aren't 10 proxies (proxychains) better than

246)     Tor with only 3 hops?</a></li>

247)     <li><a href="#AttacksOnOnionRouting">What attacks remain against onion

248)     routing?</a></li>

249)     <li><a href="#LearnMoreAboutAnonymity">Where can I learn more about anonymity?</a></li>

250)     </ul>

251) 

252)     <a id="altdesigns"></a>
253)     <h4 style="margin-bottom: 18px"><a class="anchor" href="#altdesigns">Alternate designs that we don't do (yet):</a></h4>

254) 

255)     <ul>
256)     <li><a href="#EverybodyARelay">You should make every Tor user be a
257)     relay.</a></li>

258)     <li><a href="#TransportIPnotTCP">You should transport all IP
259) packets,

260)     not just TCP packets.</a></li>

261)     <li><a href="#HideExits">You should hide the list of Tor relays,
262)     so people can't block the exits.</a></li>

263)     <li><a href="#ChoosePathLength">You should let people choose their path

264)     length.</a></li>

265)     <li><a href="#SplitEachConnection">You should split each connection over

266)     many paths.</a></li>

267)     <li><a href="#MigrateApplicationStreamsAcrossCircuits">You should migrate

268)     application streams across circuits.</a></li>

269)     <li><a href="#LetTheNetworkPickThePath">You should let the network pick

270)     the path, not the client.</a></li>

271)     <li><a href="#UnallocatedNetBlocks">Your default exit policy should block

272)     unallocated net blocks too.</a></li>

273)     <li><a href="#BlockWebsites">Exit policies should be able to block

274)     websites, not just IP addresses.</a></li>

275)     <li><a href="#BlockContent">You should change Tor to prevent users from

276)     posting certain content.</a></li>

277)     <li><a href="#SendPadding">You should send padding so it's more secure.
278)     </a></li>

279)     <li><a href="#Steganography">You should use steganography to hide Tor

280)     traffic.</a></li>

281)     </ul>

282) 

283)     <a id="abuse"></a>
284)     <h4 style="margin-bottom: 18px"><a class="anchor" href="#abuse">Abuse:</a></h4>

285)     <ul>

286)     <li><a href="#Criminals">Doesn't Tor enable criminals to do bad
287) things?</a></li>

288)     <li><a href="#RespondISP">How do I respond to my ISP about my exit
289)     relay?</a></li>

290)     <li><a href="#HelpPoliceOrLawyers">I have questions about
291)    a Tor IP address for a legal case.</a></li>

292)     </ul>

293) 

294)     <p>For other questions not yet on this version of the FAQ, see the
295) <a

296)     href="<wikifaq>">wiki FAQ</a> for now.</p>

297) 

298)     <hr>

299) 

300)     <a id="General"></a>

301)     <h2><a class="anchor" href="#General">General:</a></h2>

302) 

303)     <a id="WhatIsTor"></a>
304)     <h3><a class="anchor" href="#WhatIsTor">What is Tor?</a></h3>

305) 

306)     <p>
307)     The name "Tor" can refer to several different components.
308)     </p>

309) 

310)     <p>

311)     Tor is a program you can run on your computer that helps keep
312)     you safe on the Internet. It protects you by bouncing your communications

313)     around a distributed network of relays run by volunteers all around

314)     the world: it prevents somebody watching your Internet connection from

315)     learning what sites you visit, and it prevents the sites you visit

316)     from learning your physical location.
317)     This set of volunteer relays is called the <b>Tor network</b>.
318)     The way most people use Tor is with <b>Tor Browser</b>,
319)     which is a version of Firefox that fixes many privacy issues.
320)     You can read more about how Tor works on the <a href="<page
321)     about/overview>">overview page</a>.

322)     </p>

323) 

324)     <p>

325)     The <b>Tor Project</b> is a non-profit (charity) organization that
326)     maintains and develops the Tor software.

327)     </p>

328) 

329)     <hr>

330) 

331)     <a id="Torisdifferent"></a>

332)     <h3><a class="anchor" href="#Torisdifferent">How is Tor different
333) from other proxies?</a></h3>
334)     <p>
335)     A typical proxy provider sets up a server somewhere on the Internet
336) and
337) allows you to use it to relay your traffic.  This creates a simple, easy
338) to
339) maintain architecture.  The users all enter and leave through the same
340) server.
341) The provider may charge for use of the proxy, or fund their costs
342) through
343) advertisements on the server.  In the simplest configuration, you don't
344) have to
345) install anything.  You just have to point your browser at their proxy
346) server.
347) Simple proxy providers are fine solutions if you do not want protections
348) for

349) your privacy and anonymity online and you trust the provider to not do

350) bad
351) things.  Some simple proxy providers use SSL to secure your connection

352) to them, which protects you against local eavesdroppers, such as those at a
353) cafe with free wifi Internet.

354)     </p>
355)     <p>

356)     Simple proxy providers also create a single point of failure.  The
357) provider

358) knows both who you are and what you browse on the Internet.  They can see

359) your
360) traffic as it passes through their server.  In some cases, they can even
361) see

362) inside your

363) encrypted traffic as they relay it to your banking site or to ecommerce
364) stores.

365) You have to trust the provider isn't

366) watching your traffic, injecting their own advertisements into your
367) traffic

368) stream, or recording your personal details.

369)     </p>
370)     <p>

371)     Tor passes your traffic through at least 3 different servers before
372) sending
373) it on to the destination. Because there's a separate layer of encryption
374) for

375) each of the three relays, somebody watching your Internet connection
376) can't modify, or read, what you are
377) sending into the Tor network. Your traffic is encrypted between the Tor
378) client (on your computer) and where it pops out somewhere else in the
379) world.
380) </p>

381)     <p>
382)     <dl>

383)     <dt>Doesn't the first server see who I am?</dt><dd>Possibly. A bad
384) first of
385) three servers can see encrypted Tor traffic coming from your computer.
386) It
387) still doesn't know who you are and what you are doing over Tor.  It
388) merely sees
389) "This IP address is using Tor".  Tor is not illegal anywhere in the
390) world, so
391) using Tor by itself is fine.  You are still protected from this node
392) figuring

393) out both who you are and where you are going on the Internet.</dd>

394)     <dt>Can't the third server see my traffic?</dt><dd>Possibly.  A bad
395) third
396) of three servers can see the traffic you sent into Tor.  It won't know
397) who sent

398) this traffic.  If you're using encryption (like
399) HTTPS), it will only know the destination. See <a
400) href="https://www.eff.org/pages/tor-and-https">this visualization of
401) Tor and HTTPS</a> to understand how Tor and HTTPS interact.
402) </dd>

403)     </dl>
404)     </p>

405) 

406)     <hr>

407) 

408) 

409)     <a id="CompatibleApplications"></a>

410)     <h3><a class="anchor" href="#CompatibleApplications">What programs
411) can I use with Tor?</a></h3>

412) 

413)     <p>

414)     Most people use Tor Browser,

415)     which includes everything you need to browse the web safely using

416)     Tor. Using other browsers is <a href="#TBBOtherBrowser">dangerous
417)     and not recommended</a>.

418)     </p>
419)     <p>
420)     There are plenty of other programs you can use with Tor,
421)     but we haven't researched the application-level anonymity

422)     issues on all of them well enough to be able to recommend a safe

423)     configuration. Our wiki has a community-maintained list of
424)     instructions for <a

425)     href="<wiki>doc/TorifyHOWTO">Torifying

426)     specific applications</a>.

427)     Please add to these lists and help us keep them accurate!
428)     </p>

429) 

430)     <hr>

431) 

432)     <a id="WhyCalledTor"></a>

433)     <h3><a class="anchor" href="#WhyCalledTor">Why is it called
434) Tor?</a></h3>

435) 

436)     <p>
437)     Because Tor is the onion routing network. When we were starting the
438)     new next-generation design and implementation of onion routing in
439)     2001-2002, we would tell people we were working on onion routing,
440)     and they would say "Neat. Which one?" Even if onion routing has
441)     become a standard household term, Tor was born out of the actual <a
442)     href="http://www.onion-router.net/">onion routing project</a> run by
443)     the Naval Research Lab.
444)     </p>

445) 

446)     <p>
447)     (It's also got a fine translation from German and Turkish.)
448)     </p>

449) 

450)     <p>

451)     Note: even though it originally came from an acronym, Tor is not
452) spelled

453)     "TOR". Only the first letter is capitalized. In fact, we can usually

454)     spot people who haven't read any of our website (and have instead
455) learned
456)     everything they know about Tor from news articles) by the fact that
457) they

458)     spell it wrong.
459)     </p>

460) 

461)     <hr>

462) 

463)     <a id="Backdoor"></a>

464)     <h3><a class="anchor" href="#Backdoor">Is there a backdoor in
465) Tor?</a></h3>

466) 

467)     <p>

468)     There is absolutely no backdoor in Tor.  We know some smart lawyers
469)     who say that it's unlikely that anybody will try to make us add one
470)     in our jurisdiction (U.S.). If they do ask us, we will fight them,
471)     and (the lawyers say) probably win.

472)     </p>

473) 

474)     <p>

475)     We will <a
476)     href="https://media.ccc.de/v/31c3_-_6251_-_en_-_saal_1_-_201412301400_-_state_of_the_onion_-_jacob_-_arma">never</a>
477)     put a backdoor in Tor.

478)     We think that putting a backdoor in Tor would be tremendously

479)     irresponsible to our users, and a bad precedent for security

480)     software in general. If we ever put a deliberate backdoor in our
481)     security software, it would ruin our professional reputations.
482)     Nobody would trust our software ever again — for excellent
483)     reason!

484)     </p>

485) 

486)     <p>
487)     But that said, there are still plenty of subtle attacks
488)     people might try. Somebody might impersonate us, or break into our

489)     computers, or something like that. Tor is open source, and you

490)     should always check the source (or at least the diffs since the last
491)     release) for suspicious things. If we (or the distributors) don't
492)     give you source, that's a sure sign something funny might be going
493)     on. You should also check the <a href="<page
494)     docs/verifying-signatures>">PGP signatures</a> on the releases, to
495)     make sure nobody messed with the distribution sites.

496)     </p>

497) 

498)     <p>
499)     Also, there might be accidental bugs in Tor that could affect your

500)     anonymity. We periodically find and fix anonymity-related bugs, so

501)     make sure you keep your Tor versions up-to-date.

502)     </p>

503) 

504)     <hr>

505) 

506)     <a id="DistributingTor"></a>

507)     <h3><a class="anchor" href="#DistributingTor">Can I distribute
508) Tor?</a></h3>

509) 

510)     <p>
511)     Yes.
512)     </p>

513) 

514)     <p>

515)     The Tor software is <a href="https://www.fsf.org/">free software</a>. This
516)     means we give you the rights to redistribute the Tor software, either
517)     modified or unmodified, either for a fee or gratis. You don't have to

518)     ask us for specific permission.
519)     </p>

520) 

521)     <p>

522)     However, if you want to redistribute the Tor software you must follow our

523)     <a href="<gitblob>LICENSE">LICENSE</a>.

524)     Essentially this means that you need to include our LICENSE file along

525)     with whatever part of the Tor software you're distributing.
526)     </p>

527) 

528)     <p>

529)     Most people who ask us this question don't want to distribute just the

530)     Tor software, though. They want to distribute the <a

531)     href="<page projects/torbrowser>">Tor Browser</a>. This includes <a

532)     href="https://www.mozilla.org/en-US/firefox/organizations/">Firefox

533)     Extended Support Release</a>, and the NoScript and HTTPS-Everywhere
534)     extensions. You will need to follow the license for those programs as
535)     well. Both of those Firefox extensions are distributed under

536)     the <a href="https://www.fsf.org/licensing/licenses/gpl.html">GNU General

537)     Public License</a>, while Firefox ESR is released under the Mozilla Public
538)     License. The simplest way to obey their licenses is to include the source
539)     code for these programs everywhere you include the bundles themselves.

540)     </p>

541) 

542)     <p>

543)     Also, you should make sure not to confuse your readers about what Tor is,
544)     who makes it, and what properties it provides (and doesn't provide). See
545)     our <a href="<page docs/trademark-faq>">trademark FAQ</a> for details.

546)     </p>

547) 

548)     <hr>

549) 

550)     <a id="SupportMail"></a>

551)     <h3><a class="anchor" href="#SupportMail">How can I get
552) support?</a></h3>

553) 

554)     <p>See the <a href="<page about/contact>#support">Support section
555)     on the contact page</a>.

556) 

557)     <hr>

558) 

559)     <a id="Forum"></a>
560)     <h3><a class="anchor" href="#Forum">Is there a Tor forum?</a></h3>
561) 

562)     <p>We have a <a href="https://tor.stackexchange.com/">StackExchange

563)     page</a> that is currently in public beta.

564)     </p>
565) 
566)     <hr>
567) 

568)     <a id="WhySlow"></a>
569)     <h3><a class="anchor" href="#WhySlow">Why is Tor so slow?</a></h3>

570) 

571)     <p>
572)     There are many reasons why the Tor network is currently slow.
573)     </p>

574) 

575)     <p>

576)     Before we answer, though, you should realize that Tor is never going
577) to
578)     be blazing fast. Your traffic is bouncing through volunteers'
579) computers
580)     in various parts of the world, and some bottlenecks and network
581) latency

582)     will always be present. You shouldn't expect to see university-style
583)     bandwidth through Tor.
584)     </p>

585) 

586)     <p>

587)     But that doesn't mean that it can't be improved. The current Tor
588) network
589)     is quite small compared to the number of people trying to use it,
590) and
591)     many of these users don't understand or care that Tor can't
592) currently

593)     handle file-sharing traffic load.
594)     </p>

595) 

596)     <p>
597)     For the much more in-depth answer, see <a

598)     href="<blog>why-tor-is-slow">Roger's blog

599)     post on the topic</a>, which includes both a detailed PDF and a
600) video

601)     to go with it.
602)     </p>

603) 

604)     <p>
605)     What can you do to help?
606)     </p>

607) 

608)     <ul>

609) 

610)     <li>

611)     <a href="<page docs/tor-doc-relay>">Configure your Tor to relay
612) traffic
613)     for others</a>. Help make the Tor network large enough that we can
614) handle

615)     all the users who want privacy and security on the Internet.
616)     </li>

617) 

618)     <li>

619)     Help us make Tor more usable. We

620)     especially need people to help make it easier to configure your Tor
621)     as a relay. Also, we need help with clear simple documentation to
622)     walk people through setting it up.
623)     </li>

624) 

625)     <li>

626)     There are some bottlenecks in the current Tor network. Help us
627) design
628)     experiments to track down and demonstrate where the problems are,
629) and

630)     then we can focus better on fixing them.
631)     </li>

632) 

633)     <li>
634)     Tor needs some architectural changes too. One important change is to

635)     start providing <a href="#EverybodyARelay">better service to people
636) who
637)     relay traffic</a>. We're working on this, and we'll finish faster if
638) we

639)     get to spend more time on it.
640)     </li>

641) 

642)     <li>

643)     Help do other things so we can do the hard stuff. Please take a
644) moment
645)     to figure out what your skills and interests are, and then <a
646) href="<page

647)     getinvolved/volunteer>">look at our volunteer page</a>.
648)     </li>

649) 

650)     <li>

651)     Help find sponsors for Tor. Do you work at a company or government
652) agency

653)     that uses Tor or has a use for Internet privacy, e.g. to browse the

654)     competition's websites discreetly, or to connect back to the home
655) servers
656)     when on the road without revealing affiliations? If your
657) organization has
658)     an interest in keeping the Tor network working, please contact them
659) about
660)     supporting Tor. Without sponsors, Tor is going to become even
661) slower.

662)     </li>

663) 

664)     <li>
665)     If you can't help out with any of the above, you can still help out

666)     individually by <a href="<page donate/donate>">donating a bit of
667) money to the

668)     cause</a>. It adds up!
669)     </li>

670) 

671)     </ul>

672) 

673)     <hr>

674) 

675)     <a id="FileSharing"></a>

676)     <h3><a class="anchor" href="#FileSharing">How can I share files

677)     anonymously through Tor?</a></h3>

678) 
679)     <p>

680)     File sharing (peer-to-peer/P2P) is widely unwanted in the Tor network,
681)     and exit nodes are configured to block file sharing traffic by default.
682)     Tor is not really designed for it, and file sharing through Tor slows
683)     down everyone's browsing. Also, Bittorrent over Tor <a

684)     href="https://blog.torproject.org/blog/bittorrent-over-tor-isnt-good-idea">
685)     is not anonymous</a>!

686)     </p>
687) 
688)     <hr>
689) 

690)     <a id="Funding"></a>

691)     <h3><a class="anchor" href="#Funding">What would The Tor Project do
692) with more funding?</a></h3>

693) 

694)     <p>

695)     The Tor network's <a

696) href="https://metrics.torproject.org/networksize.html">several thousand</a>

697)     relays push <a
698) href="https://metrics.torproject.org/bandwidth.html">around 100 Gbps on
699) average</a>. We have <a
700) href="https://metrics.torproject.org/userstats-relay-country.html">millions of
701)     daily users</a>. But the Tor network is not yet self-sustaining.

702)     </p>

703) 

704)     <p>

705)     There are six main development/maintenance pushes that need
706) attention:

707)     </p>

708) 

709)     <ul>

710) 

711)     <li>
712)     Scalability: We need to keep scaling and decentralizing the Tor
713)     architecture so it can handle thousands of relays and millions of

714)     users. The upcoming stable release is a major improvement, but
715) there's

716)     lots more to be done next in terms of keeping Tor fast and stable.
717)     </li>

718) 

719)     <li>

720)     User support: With this many users, a lot of people are asking
721) questions
722)     all the time, offering to help out with things, and so on. We need
723) good
724)     clean docs, and we need to spend some effort coordinating
725) volunteers.

726)     </li>

727) 

728)     <li>

729)     Relay support: the Tor network is run by volunteers, but they still
730) need

731)     attention with prompt bug fixes, explanations when things go wrong,

732)     reminders to upgrade, and so on. The network itself is a commons,
733) and
734)     somebody needs to spend some energy making sure the relay operators
735) stay
736)     happy. We also need to work on stability on some platforms —
737) e.g.,

738)     Tor relays have problems on Win XP currently.

739)     </li>

740) 

741)     <li>

742)     Usability: Beyond documentation, we also need to work on usability
743) of the
744)     software itself. This includes installers, clean GUIs, easy
745) configuration
746)     to interface with other applications, and generally automating all
747) of

748)     the difficult and confusing steps inside Tor.
749)     Usability for privacy software has never been easy.

750)     </li>

751) 

752)     <li>
753)     Incentives: We need to work on ways to encourage people to configure
754)     their Tors as relays and exit nodes rather than just clients.

755)     <a href="#EverybodyARelay">We need to make it easy to become a
756) relay,

757)     and we need to give people incentives to do it.</a>
758)     </li>

759) 

760)     <li>
761)     Research: The anonymous communications field is full
762)     of surprises and gotchas. In our copious free time, we
763)     also help run top anonymity and privacy conferences like <a
764)     href="http://petsymposium.org/">PETS</a>. We've identified a set of

765)     critical <a href="<page getinvolved/volunteer>#Research">Tor
766) research questions</a>
767)     that will help us figure out how to make Tor secure against the
768) variety of
769)     attacks out there. Of course, there are more research questions
770) waiting

771)     behind these.
772)     </li>

773) 

774)     </ul>

775) 

776)     <p>
777)     We're continuing to move forward on all of these, but at this rate

778)     <a href="#WhySlow">the Tor network is growing faster than the
779) developers

780)     can keep up</a>.

781)     Now would be an excellent time to add a few more developers to the
782) effort

783)     so we can continue to grow the network.
784)     </p>

785) 

786)     <p>
787)     We are also excited about tackling related problems, such as
788)     censorship-resistance.
789)     </p>

790) 

791)     <p>

792)     We are proud to have <a href="<page about/sponsors>">sponsorship and
793) support</a>
794)     from the Omidyar Network, the International Broadcasting Bureau,
795) Bell
796)     Security Solutions, the Electronic Frontier Foundation, several
797) government

798)     agencies and research groups, and hundreds of private contributors.
799)     </p>

800) 

801)     <p>

802)     However, this support is not enough to keep Tor abreast of changes
803) in the
804)     Internet privacy landscape. Please <a href="<page
805) donate/donate>">donate</a>
806)     to the project, or <a href="<page about/contact>">contact</a> our
807) executive

808)     director for information on making grants or major donations.
809)     </p>

810) 

811)     <hr>
812) 
813) 
814)     <a id="Mobile"></a>

815)     <h3><a class="anchor" href="#Mobile">Can I use Tor on my phone or mobile

816)     device?</a></h3>
817) 
818)     <p>

819)     Tor on Android devices is maintained by the <a
820)     href="https://guardianproject.info">Guardian Project</a>. Currently, there
821)     is no supported way of using Tor on iOS; the Guardian Project is

822)     working to make this a reality in the future.
823)     </p>
824) 

825)     <hr>
826) 

827)     <a id="OutboundPorts"></a>
828)     <h3><a class="anchor" href="#OutboundPorts">Which outbound ports must be open when
829)     using Tor as a client?</a></h3>

830)     <p>

831)     Tor may attempt to connect to any port that is advertised in the
832)     directory as an ORPort (for making Tor connections) or a DirPort (for

833)     fetching updates to the directory). There are a variety of these ports:
834)     many of them are running on 80, 443, 9001, and 9030, but many use other
835)     ports too.

836)     </p>
837)     <p>

838)     When using Tor as a client, you could probably get away with opening only those four

839)     ports. Since Tor does all its connections in the background, it will retry
840)     ones that fail, and hopefully you'll never have to know that it failed, as
841)     long as it finds a working one often enough. However, to get the most

842)     diversity in your entry nodes — and thus the most security
843)     — as well as the most robustness in your connectivity, you'll
844)     want to let it connect to all of them.
845)     See the FAQ entry on <a href="#FirewallPorts">firewalled ports</a> if
846)     you want to explicitly tell your Tor client which ports are reachable
847)     for you.
848)     </p>

849) 

850)     <hr>

851) 

852)     <a id="IsItWorking"></a>

853)     <h3><a class="anchor" href="#IsItWorking">How can I tell if Tor is

854)     working, and that my connections really are anonymized?</a></h3>

855) 
856)     <p>

857)     There are sites you can visit that will tell you if you appear to be

858)     coming through the Tor network. Try the <a href="https://check.torproject.org">
859)     Tor Check</a> site and see whether it thinks you are using Tor or not.

860)     </p>

861) 

862)     <hr>

863) 

864)     <a id="FTP"></a>
865)     <h3><a class="anchor" href="#FTP">How do I use my browser for ftp with Tor?
866)     </a></h3>
867) 

868)     <p>

869)     Use <a href="https://torproject.org/projects/torbrowser.html">Tor
870)     Browser</a>. If you want a separate application for an

871)     ftp client, we've heard good things about  FileZilla for Windows. You can
872)     configure it to point to Tor as a "socks4a" proxy on "localhost" port
873)     "9050".

874)     </p>

875) 

876)     <hr>

877) 

878)     <a id="NoDataScrubbing"></a>

879)     <h3><a class="anchor" href="#NoDataScrubbing">Does Tor remove personal

880)     information from the data my application sends?</a></h3>
881) 

882)     <p>No, it doesn't. You need to use a separate program that understands
883)     your application and protocol and knows how to clean or "scrub" the data

884)     it sends. Tor Browser tries to keep application-level data,
885)     like the user-agent string, uniform for all users. Tor Browser can't

886)     do anything about text that you type into forms, though. <a

887)     href="<page download/download-easy>#warning">Be

888)     careful and be smart.</a>
889)     </p>
890) 
891)     <hr>
892) 

893)     <a id="Metrics"></a>

894)     <h3><a class="anchor" href="#Metrics">How many people use Tor? How

895)     many relays or exit nodes are there?</a></h3>

896) 

897)     <p>
898)     All this and more about measuring Tor can be found at the <a

899)     href="https://metrics.torproject.org/">Tor Metrics Portal</a>.</p>

900)     <hr>

901) 

902)     <a id="CompilationAndInstallation"></a>

903)     <h2><a class="anchor" href="#CompilationAndInstallation">Compilation And Installation:</a></h2>

904) 

905)     <a id="HowUninstallTor"></a>

906)     <h3><a class="anchor" href="#HowUninstallTor">How do I uninstall
907) Tor?</a></h3>
908) 
909)     <p>
910)     Tor Browser does not install itself in the classic sense of
911) applications. You just simply delete the folder or directory named "Tor
912) Browser" and it is removed from your system.
913)     </p>

914) 

915)     <p>

916)     If this is not related to Tor Browser, uninstallation depends
917) entirely on how you installed it and which operating system you
918)     have. If you installed a package, then hopefully your package has a
919) way to

920)     uninstall itself. The Windows packages include uninstallers.

921)     </p>

922) 

923)     <p>
924)     For Mac OS X, follow the <a
925)     href="<page docs/tor-doc-osx>#uninstall">uninstall directions</a>.
926)     </p>

927) 

928)     <p>

929)     If you installed by source, I'm afraid there is no easy uninstall
930) method. But
931)     on the bright side, by default it only installs into /usr/local/ and
932) it should

933)     be pretty easy to notice things there.
934)     </p>

935) 

936)     <hr>

937) 

938)     <a id="PGPSigs"></a>

939)     <h3><a class="anchor" href="#PGPSigs">What are these "sig" files on
940) the download page?</a></h3>

941) 

942)     <p>

943)     These are PGP signatures, so you can verify that the file you've
944) downloaded is

945)     exactly the one that we intended you to get.
946)     </p>

947) 

948)     <p>
949)     Please read the <a

950)     href="<page docs/verifying-signatures>">verifying signatures</a>
951) page for details.

952)     </p>

953) 

954) <hr>
955) 
956) <a id="GetTor"></a>
957) <h3><a class="anchor" href="#GetTor">Your website is blocked in my
958) country. How do I download Tor?</a></h3>
959) 
960) <p>
961) Some government or corporate firewalls censor connections to Tor's
962) website. In those cases, you have three options. First, get it from

963) a friend &mdash; <a href="<page projects/torbrowser>">Tor Browser</a>

964) fits nicely on a USB key. Second, find the <a

965) href="https://encrypted.google.com/search?q=tor+mirrors">google
966) cache</a>

967) for the <a href="<page getinvolved/mirrors>">Tor mirrors</a> page
968) and see if any of those copies of our website work for you. Third,

969) you can download Tor Browser via email: log in to your email account
970) and send an email to '<tt>gettor@torproject.org</tt>' with one of the
971) following words in the body of the message: <tt>windows</tt>,
972) <tt>osx</tt> or <tt>linux</tt> (case insensitive).
973) You will receive a reply with links from popular cloud services to

974) download Tor Browser for Windows, Mac OS X or Linux, depending on the

975) option you chose. Currently, the only cloud service supported is

976) Dropbox. If you send a blank message or anything different from the
977) options mentioned, you will receive a help message with detailed

978) instructions to ask for Tor Browser via email. Please note that you
979) can use this service from any email address: gmail, yahoo, hotmail,
980) riseup, etc. The only restriction is that you can do a maximum of
981) three requests in a row, after that you'll have to wait 20 minutes to
982) use it again. See the <a href="../projects/gettor.html">GetTor</a>
983) section for more information.

984) </p>
985) 
986) <p>

987) Be sure to <a href="<page docs/verifying-signatures>">verify the
988) signature</a>

989) of any package you download, especially when you get it from somewhere
990) other than our official HTTPS website.

991) </p>
992) 

993)     <hr>

994) 

995)     <a id="VirusFalsePositives"></a>

996)     <h3><a class="anchor" href="#VirusFalsePositives">Why does my
997)     Tor executable appear to have a virus or spyware?</a></h3>

998)     <p>

999)     Sometimes, overzealous Windows virus and spyware detectors trigger on
1000)     some parts of the Tor Windows binary. Our best guess is that these are
1001)     false positives — after all, the anti-virus and anti-spyware business is
1002)     just a guessing game anyway. You should contact your vendor and explain
1003)     that you have a program that seems to be triggering false positives. Or

1004)     pick a better vendor.
1005)     </p>

1006)     <p>In the meantime, we encourage you to not just take our word for it.
1007)     Our job is to provide the source; if you're concerned, please do

1008)     recompile it yourself.</p>
1009) 
1010)     <hr>
1011) 

1012)     <a id="tarballs"></a>

1013)     <h3><a class="anchor" href="#tarballs">How do I open a .tar.gz

1014)     or .tar.xz file?</a></h3>

1015) 
1016)     <p>
1017)     Tar is a common archive utility for Unix and Linux systems. If your

1018)     system has a mouse, you can usually open them by double clicking.
1019)     Otherwise open a command prompt and execute</p>

1020)     <pre>tar xzf &lt;FILENAME&gt;.tar.gz</pre> or <pre>tar xJf &lt;FILENAME&gt;.tar.xz</pre>

1021)     <p>

1022)     as documented on tar's man page.

1023)     </p>
1024) 
1025)     <hr>
1026) 

1027)     <a id="LiveCD"></a>

1028)     <h3><a class="anchor" href="#LiveCD">Is there a LiveCD or other
1029) bundle that includes Tor?</a></h3>

1030) 

1031)     <p>

1032)     Yes.  Use <a href="https://tails.boum.org/">The Amnesic Incognito

1033)     Live System</a> or <a href="<page projects/torbrowser>">Tor Browser</a>.

1034)     </p>

1035) 
1036) <hr>
1037) 

1038) <a id="TBBGeneral"></a>

1039) <h2><a class="anchor" href="#TBBGeneral">Tor Browser (general):</a></h2>

1040) 

1041) <a id="TBBFlash"></a>

1042) <h3><a class="anchor" href="#TBBFlash">Why can't I view videos on

1043) some Flash-based sites?</a></h3>

1044) 
1045) <p>

1046) Some sites require third party browser plugins such as Flash.

1047) Plugins operate independently from Firefox and can perform
1048) activity on your computer that ruins your anonymity. This includes

1049) but is not limited to: completely disregarding
1050) proxy settings, querying your <a

1051) href="http://forums.sun.com/thread.jspa?threadID=5162138&messageID=9618376">
1052) local IP address</a>, and <a

1053) href="http://epic.org/privacy/cookies/flash.html">storing their own
1054) cookies</a>. It is possible to use a LiveCD solution such as

1055) or <a href="https://tails.boum.org/">The Amnesic Incognito Live System</a>
1056) that creates a secure, transparent proxy to protect you from proxy bypass,
1057) however issues with local IP address discovery and Flash cookies still remain.

1058) </p>

1059) 

1060) <hr>
1061) 

1062) <a id="Ubuntu"></a>
1063) <h3><a class="anchor" href="#Ubuntu">

1064) I'm using Ubuntu and I can't start Tor Browser.</a></h3>

1065) <p>

1066) You'll need to tell Ubuntu that you want the ability to execute shell scripts
1067) from the graphical interface. Open "Files" (Unity's explorer), open
1068) Preferences-> Behavior Tab -> Set "Run executable text files when they are

1069) opened" to "Ask every time", then OK.

1070) </p>

1071) <p>You can also start Tor Browser from the command line by running </p>

1072) <pre>./start-tor-browser</pre>

1073) <p>
1074) from inside the Tor Browser directory.
1075) </p>
1076) 

1077) <hr>
1078) 

1079) <a id="SophosOnMac"></a>
1080) <h3><a class="anchor" href="#SophosOnMac">I'm using the Sophos anti-virus

1081)     software on my Mac, and Tor starts but I can't browse anywhere.</a></h3>

1082) <p>

1083) You'll need to modify Sophos anti-virus so that Tor can connect to the
1084) internet. Go to Preferences -> Web Protection -> General, and turn off

1085) the protections for "Malicious websites" and "Malicious downloads".
1086) </p>

1087) <p>

1088) We encourage affected Sophos users to contact Sophos support about

1089) this issue.
1090) </p>

1091) 

1092) <hr>
1093) 

1094) <a id="XPCOMError"></a>

1095) <h3><a class="anchor" href="#XPCOMError">When I start Tor Browser I get an 
1096) error message: "Cannot load XPCOM".</a></h3>

1097) 
1098) <p>

1099) This <a 
1100) href="https://trac.torproject.org/projects/tor/ticket/10789">problem</a> is 
1101) specifically caused by the Webroot SecureAnywhere Antivirus software. 
1102) From the Webroot control panel, go to Identity Protection &rarr; Application 
1103) Protection, and set all the files in your Tor Browser folder to 'Allow'. 
1104) We encourage affected Webroot users to contact Webroot support about this 
1105) issue.

1106) </p>

1107) 
1108) <hr>
1109) 

1110) <a id="TBBOtherExtensions"></a>
1111) <h3><a class="anchor" href="#TBBOtherExtensions">Can I install other
1112) Firefox extensions?</a></h3>
1113) 
1114) <p>

1115) Tor Browser is free software, so there is nothing preventing you from

1116) modifying it any way you like. However, we do not recommend installing any

1117) additional Firefox add-ons with Tor Browser. Add-ons can break

1118) your anonymity in a number of ways, including browser fingerprinting and

1119) bypassing proxy settings.

1120) </p>

1121) <p>

1122) Some people have suggested we include ad-blocking software or

1123) anti-tracking software with Tor Browser. Right now, we do not

1124) think that's such a good idea. Tor Browser aims to provide

1125) sufficient privacy that additional add-ons to stop ads and trackers are
1126) not necessary. Using add-ons like these may cause some sites to break, which

1127) <a href="https://www.torproject.org/projects/torbrowser/design/#philosophy">

1128) we don't want to do</a>. Additionally, maintaining a list of "bad" sites that
1129) should be black-listed provides another opportunity to uniquely fingerprint
1130) users.

1131) </p>

1132) 

1133) <hr>
1134) 

1135) <a id="TBBJavaScriptEnabled"></a>

1136) <a id="TBBCanIBlockJS"></a>

1137) <h3><a class="anchor" href="#TBBJavaScriptEnabled">Why is NoScript

1138) configured to allow JavaScript by default in Tor Browser?

1139) Isn't that unsafe?</a></h3>

1140) 
1141) <p>

1142) We configure NoScript to allow JavaScript by default in Tor
1143) Browser because many websites will not work with JavaScript

1144) disabled.  Most users would give up on Tor entirely if a website
1145) they want to use requires JavaScript, because they would not know
1146) how to allow a website to use JavaScript (or that enabling
1147) JavaScript might make a website work).
1148) </p>
1149) 

1150) <p>
1151) There's a tradeoff here. On the one hand, we should leave
1152) JavaScript enabled by default so websites work the way
1153) users expect. On the other hand, we should disable JavaScript
1154) by default to better protect against browser vulnerabilities (<a

1155) href="https://blog.torproject.org/blog/tor-security-advisory-old-tor-browser-bundles-vulnerable">
1156) not just a theoretical concern!</a>). But there's a third issue: websites

1157) can easily determine whether you have allowed JavaScript for them,
1158) and if you disable JavaScript by default but then allow a few websites
1159) to run scripts (the way most people use NoScript), then your choice of
1160) whitelisted websites acts as a sort of cookie that makes you recognizable
1161) (and distinguishable), thus harming your anonymity.
1162) </p>

1163) 
1164) <p>

1165) Ultimately, we want the default Tor bundles to use
1166) a combination of firewalls (like the iptables rules
1167) in <a href="https://tails.boum.org/">Tails</a>) and <a
1168) href="https://trac.torproject.org/projects/tor/ticket/7680">sandboxes</a>
1169) to make JavaScript not so scary. In
1170) the shorter term, TBB 3.0 will hopefully <a
1171) href="https://trac.torproject.org/projects/tor/ticket/9387">allow users
1172) to choose their JavaScript settings more easily</a> &mdash; but the
1173) partitioning concern will remain.

1174) </p>
1175) 
1176) <p>

1177) Until we get there, feel free to leave JavaScript on or off depending
1178) on your security, anonymity, and usability priorities.

1179) </p>
1180) 
1181) <hr>
1182) 

1183) <a id="TBBOtherBrowser"></a>
1184) <h3><a class="anchor" href="#TBBOtherBrowser">I want to use
1185) Chrome/IE/Opera/etc with Tor.</a></h3>
1186) 
1187) <p>

1188) In short, using any browser besides Tor Browser with Tor is a

1189) really bad idea.
1190) </p>
1191) 
1192) <p>

1193) Our efforts to work with the Chrome team to <a
1194) href="https://blog.torproject.org/blog/google-chrome-incognito-mode-tor-and-fingerprinting">add
1195) missing APIs</a> were unsuccessful, unfortunately. Currently, it is impossible

1196) to use other browsers and get the same level of protections as when using

1197) Tor Browser.

1198) </p>
1199) 
1200) <hr>
1201) 

1202) <a id="GoogleCAPTCHA"></a>
1203) <h3><a class="anchor" href="#GoogleCAPTCHA">Google makes me solve a
1204) CAPTCHA or tells me I have spyware installed.</a></h3>

1205) 
1206) <p>
1207) This is a known and intermittent problem; it does not mean that Google
1208) considers Tor to be spyware.
1209) </p>
1210) 
1211) <p>

1212) When you use Tor, you are sending queries through exit relays that are

1213) also shared by thousands of other users. Tor users typically see this
1214) message when many Tor users are querying Google in a short period of time.
1215) Google interprets the high volume of traffic from a single IP address
1216) (the exit relay you happened to pick) as somebody trying to "crawl" their
1217) website, so it slows down traffic from that IP address for a short time.

1218) </p>
1219) <p>
1220) An alternate explanation is that Google tries to detect certain
1221) kinds of spyware or viruses that send distinctive queries to Google
1222) Search. It notes the IP addresses from which those queries are received
1223) (not realizing that they are Tor exit relays), and tries to warn any
1224) connections coming from those IP addresses that recent queries indicate
1225) an infection.
1226) </p>
1227) 
1228) <p>

1229) To our knowledge, Google is not doing anything intentionally specifically

1230) to deter or block Tor use. The error message about an infected machine
1231) should clear up again after a short time.
1232) </p>
1233) 
1234) <hr />
1235) 

1236) <a id="ForeignLanguages"></a>
1237) <h3><a class="anchor" href="#ForeignLanguages">
1238) Why does Google show up in foreign languages?</a></h3>
1239) 
1240) <p>

1241)  Google uses "geolocation" to determine where in the world you are, so it
1242)  can give you a personalized experience. This includes using the language
1243)  it thinks you prefer, and it also includes giving you different results

1244)  on your queries.

1245) </p>
1246) <p>

1247) If you really want to see Google in English you can click the link that
1248) provides that. But we consider this a feature with Tor, not a bug --- the
1249) Internet is not flat, and it in fact does look different depending on

1250) where you are. This feature reminds people of this fact.

1251) </p>
1252) <p>

1253) Note that Google search URLs take name/value pairs as arguments and one
1254) of those names is "hl". If you set "hl" to "en" then Google will return
1255) search results in English regardless of what Google server you have been
1256) sent to. On a query this looks like:

1257) </p>

1258) <pre>https://encrypted.google.com/search?q=online%20anonymity&hl=en</pre>

1259) <p>

1260) Another method is to simply use your country code for accessing Google.
1261) This can be google.be, google.de, google.us and so on.

1262) </p>
1263) <hr />

1264) <a id="GmailWarning"></a>

1265) <h3><a class="anchor" href="#GmailWarning">Gmail warns me that my

1266) account may have been compromised.</a></h3>

1267) 
1268) <p>
1269) Sometimes, after you've used Gmail over Tor, Google presents a
1270) pop-up notification that your account may have been compromised.
1271) The notification window lists a series of IP addresses and locations
1272) throughout the world recently used to access your account.
1273) </p>
1274) 
1275) <p>
1276) In general this is a false alarm: Google saw a bunch of logins from

1277) different places, as a result of running the service via Tor, and
1278) decided

1279) it was a good idea to confirm the account was being accessed by it's
1280) rightful owner.
1281) </p>
1282) 
1283) <p>
1284) Even though this may be a biproduct of using the service via tor,
1285) that doesn't mean you can entirely ignore the warning. It is
1286) <i>probably</i> a false positive, but it might not be since it is
1287) possible for someone to hijack your Google cookie.
1288) </p>
1289) 
1290) <p>
1291) Cookie hijacking is possible by either physical access to your computer
1292) or by watching your network traffic.  In theory only physical access
1293) should compromise your system because Gmail and similar services
1294) should only send the cookie over an SSL link. In practice, alas, it's <a

1295) href="http://fscked.org/blog/fully-automated-active-https-cookie-
1296) hijacking">

1297) way more complex than that</a>.
1298) </p>
1299) 
1300) <p>
1301) And if somebody <i>did</i> steal your google cookie, they might end
1302) up logging in from unusual places (though of course they also might
1303) not). So the summary is that since you're using Tor, this security
1304) measure that Google uses isn't so useful for you, because it's full of
1305) false positives. You'll have to use other approaches, like seeing if
1306) anything looks weird on the account, or looking at the timestamps for
1307) recent logins and wondering if you actually logged in at those times.
1308) </p>
1309) 
1310) <hr>
1311) 

1312) <a id="NeedToUseAProxy"></a>

1313) <h3><a class="anchor" href="#NeedToUseAProxy">My internet connection

1314) requires an HTTP or SOCKS Proxy</a></h3>

1315) 
1316) <p>

1317) You can set Proxy IP address, port, and authentication information in
1318) Tor Browser's Network Settings. If you're using Tor another way, check
1319) out the HTTPProxy and HTTPSProxy config options in the <a

1320) href="<page docs/tor-manual>">man page</a>,

1321) and modify your torrc file accordingly. You will need an HTTP proxy for
1322) doing GET requests to fetch the Tor directory, and you will need an
1323) HTTPS proxy for doing CONNECT requests to get to Tor relays. (It's fine
1324) if they're the same proxy.) Tor also recognizes the torrc options
1325) Socks4Proxy and Socks5Proxy.

1326) </p>
1327) <p>

1328) Also read up on the HTTPProxyAuthenticator and HTTPSProxyAuthenticator
1329) options if your proxy requires auth. We only support basic auth currently,
1330) but if you need NTLM authentication, you may find <a
1331) href="http://archives.seul.org/or/talk/Jun-2005/msg00223.html">this post
1332) in the archives</a> useful.

1333) </p>
1334) <p>

1335) If your proxies only allow you to connect to certain ports, look at the
1336) entry on <a href="#FirewallPorts">Firewalled clients</a> for how
1337) to restrict what ports your Tor will try to access.

1338) </p>
1339) 
1340) <hr>
1341) 

1342) 
1343) <a id="TBBSocksPort"></a>
1344) <h3><a class="anchor" href="#TBBSocksPort">
1345) I want to run another application through Tor.</a></h3>
1346) 
1347) <p>
1348) If you are trying to use some external application with Tor, step zero
1349) should be to <a href="<page download/download>#warning">reread the set
1350) of warnings</a> for ways you can screw up. Step one should be to try
1351) to use a SOCKS proxy rather than an HTTP proxy.
1352) Typically Tor listens for SOCKS connections on port 9050. Tor Browser listens
1353) on port 9150.
1354) </p>
1355) 
1356) <p>
1357) If your application doesn't support SOCKS proxies, feel free to install <a
1358) href="http://www.privoxy.org/">privoxy</a>.
1359) However, please realize that this approach is not recommended for novice
1360) users. Privoxy has an <a
1361) href="http://www.privoxy.org/faq/misc.html#TOR">example
1362) configuration</a> of Tor and Privoxy.
1363) </p>
1364) 
1365) <p>

1366) If you're unable to use the application's native proxy settings, all hope is

1367) not lost. See <a href="#CantSetProxy">below</a>.
1368) </p>
1369) 
1370) <hr>
1371) 

1372) <a id="CantSetProxy"></a>

1373) <h3><a class="anchor" href="#CantSetProxy">What should I do if I can't

1374) set a proxy with my application?</a></h3>
1375) 
1376) <p>

1377) On Unix, we recommend you give <a
1378) href="https://github.com/dgoulet/torsocks/">torsocks</a> a try.
1379) Alternative proxifying tools like <a
1380) href="http://www.dest-unreach.org/socat/">socat</a> and <a
1381) href="http://proxychains.sourceforge.net/">proxychains</a> are also

1382) available.</p>

1383) <p>
1384) The Windows way to force applications through Tor is less clear. <a
1385) href="http://freecap.ru/eng/">Some</a> <a
1386) href="http://www.freehaven.net/~aphex/torcap/">tools</a> have been <a

1387) href="http://www.crowdstrike.com/community-tools/index.html#tool-79">proposed

1388) </a>, but we'd also like to see further testing done here.

1389) </p>
1390) 
1391) <hr>
1392) 

1393) <a id="TBB3.x"></a>

1394) <h2><a class="anchor" href="#TBB3.x">Tor Browser (3.x and later):</a></h2>

1395)     <a id="WhereDidVidaliaGo"></a>

1396)     <h3><a class="anchor" href="#WhereDidVidaliaGo">Where did the world map

1397)     (Vidalia) go?</a></h3>
1398) 

1399)     <p>Vidalia has been replaced with Tor Launcher, which is a Firefox

1400)     extension that provides similar functionality.</p>

1401) 
1402)     <hr>
1403) 
1404)     <a id="DisableJS"></a>
1405)     <h3><a class="anchor" href="#DisableJS">How do I disable JavaScript?</a>
1406)     </h3>
1407) 

1408)     <p>Alas, Mozilla decided to get rid of the config checkbox for JavaScript
1409)     from earlier Firefox versions. And since TBB 3.5 is based on Firefox 24
1410)     (FF17 is unmaintained), that means TBB 3.5 doesn't have the config

1411)     checkbox anymore either, which is unfortunate.</p>
1412) 

1413)     <p>The simplest way to disable JavaScript in TBB 3.5 is to click on the
1414)     Noscript "S" (between the green onion and the address bar), and select
1415)     "Forbid scripts globally". Note that vanilla NoScript actually whitelists
1416)     several domains even when you try to disable scripts globally, whereas

1417)     Tor Browser's NoScript configuration disables all of them. </p>
1418) 

1419)     <p>The more klunky way to disable JavaScript is to go to about:config,

1420)     find javascript.enabled, and set it to false.</p>
1421) 
1422)     <p>There is also a very simple addon available at addons.mozilla.org
1423)     called QuickJS, which provides a toolbar toggle for the javascript.enabled

1424)     about:config control. There are no configuration options for the addon,
1425)     it just switches the javascript.enabled entry between true and false and

1426)     provides a button for it. </p>
1427) 

1428)     <p>If you want to be extra safe, use both the about:config setting and

1429)     NoScript. </p>
1430) 

1431)     <p>As for whether you should disable it or leave it enabled, that's <a

1432)     href="#TBBJavaScriptEnabled">a tradeoff we leave to you</a>.</p>

1433) 
1434)     <hr>
1435) 
1436)     <a id="VerifyDownload"></a>
1437)     <h3><a class="anchor" href="#VerifyDownload">How do I verify the download
1438)     (sha256sums.txt)?</a></h3>
1439) 

1440)     <p>Instructions are on the <a
1441)     href="<page docs/verifying-signatures>#BuildVerification">verifying

1442)     signatures</a> page.</p>

1443) 
1444)     <hr>

1445) 

1446)     <a id="NewIdentityClosingTabs"></a>

1447)     <h3><a class="anchor" href="#NewIdentityClosingTabs">Why does "New

1448)     Identity" close all my open tabs?</a></h3>
1449) 
1450)     <p>

1451)     That's actually a feature, since it's discarding your application-level

1452)     browser data too.

1453)     </p>
1454) 
1455)     <p>

1456)     We're working on ways to make the behavior less surprising, e.g. a popup
1457)     warning or auto restoring tabs. See ticket <a
1458)     href="https://trac.torproject.org/projects/tor/ticket/9906">#9906</a> and
1459)     ticket <a
1460)     href="https://trac.torproject.org/projects/tor/ticket/10400">#10400</a>
1461)     to follow progress there.

1462)     </p>
1463) 
1464)     <hr>
1465) 
1466)     <a id="ConfigureRelayOrBridge"></a>
1467)     <h3><a class="anchor" href="#ConfigureRelayOrBridge">How do I configure Tor as a relay or bridge?</a></h3>
1468) 
1469)     <p>

1470)     You've got three options.

1471)     </p>
1472) 
1473)     <p>

1474)     First (best option), if you're on Linux, you can install the system
1475)     Tor package (e.g. apt-get install tor) and then set it up to be a relay
1476)     (<a href="https://www.torproject.org/docs/tor-relay-debian">instructions</a>).

1477)     You can then use TBB independent of that.
1478)     </p>
1479) 
1480) 
1481)     <p>

1482)     Second (complex option), you can edit your torrc file (in Data/Tor/torrc)

1483)     directly to add the following lines:

1484)     </p>
1485)     <pre>
1486)     ORPort 443
1487)     Exitpolicy reject *:*
1488)     BridgeRelay 1  # only add this line if you want to be a bridge
1489)     </pre>
1490) 
1491)     <hr>
1492) 
1493)     <a id="Timestamps"></a>

1494)     <h3><a class="anchor" href="#Timestamps">Why are the file timestamps

1495)     from 2000?</a></h3>
1496) 

1497)     <p>One of the huge new features in TBB 3.x is the "deterministic build"

1498)     process, which allows many people to build Tor Browser and

1499)     verify that they all make exactly the same package. See Mike's <a
1500)     href="https://blog.torproject.org/blog/deterministic-builds-part-one-cyberwar-and-global-compromise">first
1501)     blog</a> post for the motivation, and his <a

1502)     href="https://blog.torproject.org/blog/deterministic-builds-part-two-technical-details">second

1503)     blog post</a> for the technical details of how we do it.

1504)     </p>
1505) 

1506)     <p>Part of creating identical builds is having everybody use the same
1507)     timestamp. Mike picked the beginning of 2000 for that time. The reason

1508)     you might see 7pm in 1999 is because of time zones. </p>
1509) 
1510)     <hr>
1511) 

1512)     <a id="TBBSourceCode"></a>

1513)     <h3><a class="anchor" href="#TBBSourceCode">Where is the source code for

1514)     Tor Browser? How do I verify a build?</a></h3>

1515) 
1516)     <p>

1517)     Tor Browser is built from the <a href="https://gitweb.torproject.org/builders/tor-browser-build.git/">tor-browser-build.git git repository</a>. You can have a look at the <a href="https://gitweb.torproject.org/builders/tor-browser-build.git/tree/README">README file</a> for the build instructions. There is also some informations in the <a href="https://trac.torproject.org/projects/tor/wiki/doc/TorBrowser/Hacking">Tor Browser Hacking Guide</a>.

1518)     </p>
1519) 
1520) 

1521) <hr>
1522) 

1523) <a id="AdvancedTorUsage"></a>

1524) <h2><a class="anchor" href="#AdvancedTorUsage">Advanced Tor usage:</a></h2>

1525) 

1526) <a id="torrc"></a>

1527) <h3><a class="anchor" href="#torrc">I'm supposed to "edit my torrc".
1528) What does that mean?</a></h3>

1529) 
1530) <p>

1531) Tor uses a text file called torrc that contains configuration

1532) instructions for how your Tor program should behave. The default

1533) configuration should work fine for most Tor users.

1534) </p>

1535) <p>

1536) If you installed Tor Browser on Windows or Linux, look for

1537) <code>Browser/TorBrowser/Data/Tor/torrc</code> inside your Tor Browser
1538) directory.

1539) If you're on macOS, the torrc is in <code>~/Library/Application Support/TorBrowser-Data/Tor</code> .
1540) To get to it, press cmd-shift-g while in Finder and copy/paste that directory
1541) into the box that appears.

1542) </p>
1543) <p>

1544) Otherwise, if you are using Tor without Tor Browser, it looks for the
1545) torrc file in <code>/usr/local/etc/tor/torrc</code> if you compiled tor
1546) from source, and <code>/etc/tor/torrc</code> or <code>/etc/torrc</code>
1547) if you installed a pre-built package.
1548) </p>

1549) 
1550) <p>

1551) Once you've created or changed your torrc file, you will need to restart
1552) tor for the changes to take effect. (For advanced users, note that

1553) you actually only need to send Tor a HUP signal, not actually restart
1554) it.)

1555) </p>
1556) 
1557) <p>

1558) For other configuration options you can use, see the <a href="<page

1559) docs/tor-manual>">Tor manual page</a>. Have a look at <a

1560) href="https://gitweb.torproject.org/tor.git/tree/src/config/torrc.sample.in">

1561) the sample torrc file</a> for hints on common configurations. Remember, all
1562) lines beginning with # in torrc are treated as comments and have no effect

1563) on Tor's configuration.

1564) </p>
1565) 
1566) <hr>
1567) 

1568) <a id="Logs"></a>

1569) <h3><a class="anchor" href="#Logs">How do I set up logging, or see Tor's
1570) logs?</a></h3>

1571) 
1572) <p>

1573) You'll have to go find the log files by

1574) hand. Here are some likely places for your logs to be:

1575) </p>
1576) 
1577) <ul>
1578) <li>On OS X, Debian, Red Hat, etc, the logs are in /var/log/tor/
1579) </li>

1580) <li>On Windows, there are no default log files currently. If you enable
1581) logs in your torrc file, they default to <code>\username\Application
1582) Data\tor\log\</code> or <code>\Application Data\tor\log\</code>
1583) </li>
1584) <li>If you compiled Tor from source, by default your Tor logs to <a
1585) href="http://en.wikipedia.org/wiki/Standard_streams">"stdout"</a>
1586) at log-level notice. If you enable logs in your torrc file, they
1587) default to <code>/usr/local/var/log/tor/</code>.

1588) </li>
1589) </ul>
1590) 
1591) <p>

1592) To change your logging setup by hand, <a href="#torrc">edit your
1593) torrc</a>

1594) and find the section (near the top of the file) which contains the
1595) following line:

1596) </p>
1597) 
1598) <pre>

1599) \## Logs go to stdout at level "notice" unless redirected by something
1600) \## else, like one of the below lines.

1601) </pre>

1602) 
1603) <p>

1604) For example, if you want Tor to send complete debug, info, notice, warn,

1605) and err level messages to a file, append the following line to the end
1606) of the section:
1607) </p>
1608) 
1609) <pre>
1610) Log debug file c:/program files/tor/debug.log
1611) </pre>
1612) 
1613) <p>

1614) Replace <code>c:/program files/tor/debug.log</code> with a directory
1615) and filename for your Tor log.

1616) </p>
1617) 
1618) <hr>
1619) 

1620) 
1621) <a id="LogLevel"></a>
1622) <h3><a class="anchor" href="#LogLevel">What log level should I use?</a></h3>
1623) 
1624) <p>

1625) There are five log levels (also called "log severities") you might see in

1626) Tor's logs:

1627) </p>
1628) 
1629) <ul>

1630)     <li>"err": something bad just happened, and we can't recover. Tor will

1631)     exit.</li>

1632)     <li>"warn": something bad happened, but we're still running. The bad
1633)     thing might be a bug in the code, some other Tor process doing something
1634)     unexpected, etc. The operator should examine the message and try to

1635)     correct the problem.</li>

1636)     <li>"notice": something the operator will want to know about.</li>

1637)     <li>"info": something happened (maybe bad, maybe ok), but there's

1638)     nothing you need to (or can) do about it.</li>

1639)     <li>"debug": for everything louder than info. It is quite loud indeed.</li>

1640) </ul>
1641) 
1642) <p>

1643) Alas, some of the warn messages are hard for ordinary users to correct -- the
1644) developers are slowly making progress at making Tor automatically react

1645) correctly for each situation.

1646) </p>
1647) 
1648) <p>

1649) We recommend running at the default, which is "notice". You will hear about

1650) important things, and you won't hear about unimportant things.

1651) </p>
1652) 
1653) <p>

1654) Tor relays in particular should avoid logging at info or debug in normal
1655) operation, since they might end up recording sensitive information in
1656) their logs.

1657) </p>
1658) 

1659) <hr>
1660) 

1661) <a id="DoesntWork"></a>

1662) <h3><a class="anchor" href="#DoesntWork">I installed Tor but it's not
1663) working.</a></h3>

1664) 
1665) <p>

1666) Once you've got Tor Browser up and running, the first question to

1667) ask is whether your Tor client is able to establish a circuit.

1668) </p>
1669) 

1670) <p>If Tor can establish a circuit, Tor Browser will
1671) automatically launch the browser for you. You can also check in the
1672) <a href="#Logs">Tor logs</a> for

1673) a line saying that Tor "has successfully opened a circuit. Looks like
1674) client functionality is working."
1675) </p>
1676) 
1677) <p>
1678) If Tor can't establish a circuit, here are some hints:
1679) </p>
1680) 
1681) <ol>
1682) <li>Check your system clock. If it's more than a few hours off, Tor will

1683) refuse to build circuits. For Microsoft Windows users, synchronize your
1684) clock under the clock -> Internet time tab. In addition, correct the

1685) day and date under the 'Date & Time' Tab. Also make sure your time
1686) zone is correct.</li>

1687) <li>Is your Internet connection <a href="#FirewallPorts">firewalled
1688) by port</a>, or do you normally need to use a <a

1689) href="<#NeedToUseAProxy">proxy</a>?

1690) </li>

1691) <li>Are you running programs like Norton Internet Security or SELinux
1692) that

1693) block certain connections, even though you don't realize they do? They
1694) could be preventing Tor from making network connections.</li>
1695) <li>Are you in China, or behind a restrictive corporate network firewall
1696) that blocks the public Tor relays? If so, you should learn about <a

1697) href="<page docs/bridges>">Tor bridges</a>.</li>

1698) <li>Check your <a href="#Logs">Tor logs</a>. Do they give you any hints
1699) about what's going wrong?</li>

1700) </ol>
1701) 
1702) <hr />
1703) 

1704) <a id="TorCrash"></a>
1705) <h3><a class="anchor" href="#TorCrash">My Tor keeps crashing.</a></h3>
1706) <p>

1707)  We want to hear from you! There are supposed to be zero crash bugs in Tor.
1708)  This FAQ entry describes the best way for you to be helpful to us. But even
1709)  if you can't work out all the details, we still want to hear about it, so
1710)  we can help you track it down.

1711) </p>
1712) <p>

1713) First, make sure you're using the latest version of Tor (either the latest
1714) stable or the latest development version).

1715) </p>
1716) <p>

1717) Second, make sure your version of libevent is new enough. We recommend at
1718) least libevent 1.3a.

1719) </p>
1720) <p>

1721) Third, see if there's already an entry for your bug in the <a
1722) href="https://bugs.torproject.org/">Tor bugtracker</a>. If so,
1723) check if there are any new details that you can add.

1724) </p>
1725) <p>

1726) Fourth, is the crash repeatable? Can you cause the crash? Can
1727) you isolate some of the circumstances or config options that
1728) make it happen? How quickly or often does the bug show up?
1729) Can you check if it happens with other versions of Tor, for
1730) example the latest stable release?

1731) </p>
1732) <p>

1733) Fifth, what sort of crash do you get?

1734) </p>
1735) <ul>
1736) <li>

1737) Does your Tor log include an "assert failure"? If so, please
1738) tell us that line, since it helps us figure out what's going on.
1739) Tell us the previous couple of log messages as well, especially
1740) if they seem important.

1741) </li>
1742) <li>

1743) If it says "Segmentation fault - core dumped" then you need to
1744) do a bit more to track it down. Look for a file like "core" or
1745) "tor.core" or "core.12345" in your current directory, or in your
1746) Data Directory. If it's there, run "gdb tor core" and then "bt",
1747) and include the output. If you can't find a core, run "ulimit -c
1748) unlimited", restart Tor, and try to make it crash again. (This core
1749) thing will only work on Unix -- alas, tracking down bugs on Windows
1750) is harder. If you're on Windows, can you get somebody to duplicate

1751) your bug on Unix?)
1752) </li>
1753) <li>

1754) If Tor simply vanishes mysteriously, it probably is a segmentation
1755) fault but you're running Tor in the background (as a daemon) so you
1756) won't notice. Go look at the end of your log file, and look for a
1757) core file as above. If you don't find any good hints, you should
1758) consider running Tor in the foreground (from a shell) so you can
1759) see how it dies. Warning: if you switch to running Tor in the foreground,
1760) you might start using a different torrc file, with a different default
1761) Data Directory; see the <a href="#UpgradeOrMove">relay-upgrade FAQ entry</a>
1762) for details.

1763) </li>
1764) <li>

1765) If it's still vanishing mysteriously, perhaps something else is killing it?
1766) Do you have resource limits (ulimits) configured that kill off processes

1767) sometimes? On Linux, try running

1768) "dmesg" to see if the out-of-memory killer removed your process. (Tor will
1769) exit cleanly if it notices that it's run out of memory, but in some cases
1770) it might not have time to notice.) In very rare circumstances, hardware
1771) problems could also be the culprit.

1772) </li>
1773) </ul>
1774) <p>

1775) Sixth, if the above ideas don't point out the bug, consider increasing your
1776) log level to "loglevel debug". You can look at the log-configuration FAQ
1777) entry for instructions on what to put in your torrc file. If it usually
1778) takes a long time for the crash to show up, you will want to reserve a whole
1779) lot of disk space for the debug log. Alternatively, you could just send
1780) debug-level logs to the screen (it's called "stdout" in the torrc), and then
1781) when it crashes you'll see the last couple of log lines it had printed.
1782) (Note that running with verbose logging like this will slow Tor down
1783) considerably, and note also that it's generally not a good idea security-wise
1784) to keep logs like this sitting around.)

1785) </p>
1786) 
1787) <hr />
1788) 

1789)     <a id="ChooseEntryExit"></a>

1790)     <h3><a class="anchor" href="#ChooseEntryExit">Can I control which
1791) nodes (or country) are used for entry/exit?</a></h3>

1792) 

1793)     <p>

1794)     Yes. You can set preferred entry and exit nodes as well as
1795)     inform Tor which nodes you do not want to use.

1796)     The following options can be added to your config file <a
1797)     href="#torrc">"torrc"</a> or specified on the command line:

1798)     </p>
1799)     <dl>
1800)       <dt><tt>EntryNodes $fingerprint,$fingerprint,...</tt></dt>

1801)         <dd>A list of preferred nodes to use for the first hop in the
1802) circuit, if possible.

1803)         </dd>
1804)       <dt><tt>ExitNodes $fingerprint,$fingerprint,...</tt></dt>

1805)         <dd>A list of preferred nodes to use for the last hop in the
1806) circuit, if possible.

1807)         </dd>
1808)       <dt><tt>ExcludeNodes $fingerprint,$fingerprint,...</tt></dt>

1809)         <dd>A list of nodes to never use when building a circuit.

1810)         </dd>
1811)       <dt><tt>ExcludeExitNodes $fingerprint,$fingerprint,...</tt></dt>

1812)         <dd>A list of nodes to never use when picking an exit.

1813)             Nodes listed in <tt>ExcludeNodes</tt> are automatically in
1814) this list.

1815)         </dd>
1816)     </dl>
1817)     <p>

1818)     <em>We recommend you do not use these</em>

1819)     — they are intended for testing and may disappear in future
1820) versions.

1821)     You get the best security that Tor can provide when you leave the
1822)     route selection to Tor; overriding the entry / exit nodes can mess
1823)     up your anonymity in ways we don't understand.

1824)     </p>
1825)     <p>

1826)     Note also that not every circuit is used to deliver traffic outside of
1827)     the Tor network. It is normal to see non-exit circuits (such as those

1828)     used to connect to onion services, those that do directory fetches,

1829)     those used for relay reachability self-tests, and so on) that end at
1830)     a non-exit node. To keep a node from being used entirely, see
1831)     <tt>ExcludeNodes</tt> and <tt>StrictNodes</tt> in the

1832)     <a href="<page docs/tor-manual>">manual</a>.

1833)     </p>
1834)     <p>

1835)     Instead of <tt>$fingerprint</tt> you can also specify a <a

1836) 
1837) href="https://secure.wikimedia.org/wikipedia/en/wiki/ISO_3166-1_alpha-2"
1838) >2

1839)     letter ISO3166 country code</a> in curly braces (for example <tt>{de}</tt>),

1840)     or an ip address pattern (for example 255.254.0.0/8).
1841)     Make sure there are no spaces between the commas and the

1842)     list items.

1843)     </p>
1844)     <p>

1845)     If you want to access a service directly through Tor's Socks
1846) interface

1847)     (eg. using ssh via connect.c), another option is to set up an

1848)     internal mapping in your configuration file using
1849) <tt>MapAddress</tt>.

1850)     See the manual page for details.
1851)     </p>

1852) 

1853)     <hr>

1854) 

1855) <a id="FirewallPorts"></a>

1856) <h3><a class="anchor" href="#FirewallPorts">My firewall only allows a
1857) few outgoing ports.</a></h3>

1858) 
1859) <p>
1860) If your firewall works by blocking ports, then you can tell Tor to only

1861) use the ports when you start your Tor Browser. Or you can add the ports
1862) that your firewall permits by adding "FascistFirewall 1"

1863) to

1864) your <a href="<page docs/faq>#torrc">torrc

1865) configuration file</a>.

1866) By default, when you set this Tor assumes that your firewall allows only
1867) port 80 and port 443 (HTTP and HTTPS respectively). You can select a
1868) different set of ports with the FirewallPorts torrc option.
1869) </p>
1870) 
1871) <p>
1872) If you want to be more fine-grained with your controls, you can also
1873) use the ReachableAddresses config options, e.g.:
1874) </p>
1875) 
1876) <pre>
1877)   ReachableDirAddresses *:80
1878)   ReachableORAddresses *:443
1879) </pre>
1880) 
1881) <hr>

1882) 

1883)     <a id="DefaultExitPorts"></a>

1884)     <h3><a class="anchor" href="#DefaultExitPorts">Is there a list of default exit

1885)     ports?</a></h3>

1886)     <p>

1887) The default open ports are listed below but keep in mind that, any port or
1888) ports can be opened by the relay operator by configuring it in torrc or
1889) modifying the source code. But the default according to src/or/policies.c
1890) from the source code release tor-0.2.4.16-rc is:

1891)     </p>
1892)     <pre>
1893)   reject 0.0.0.0/8
1894)   reject 169.254.0.0/16
1895)   reject 127.0.0.0/8
1896)   reject 192.168.0.0/16
1897)   reject 10.0.0.0/8
1898)   reject 172.16.0.0/12
1899)   reject *:25
1900)   reject *:119
1901)   reject *:135-139
1902)   reject *:445
1903)   reject *:563
1904)   reject *:1214
1905)   reject *:4661-4666
1906)   reject *:6346-6429
1907)   reject *:6699
1908)   reject *:6881-6999
1909)   accept *:*
1910)     </pre>
1911)     <p>

1912)     A relay will block access to its own IP address, as well local network
1913)     IP addresses. A relay always blocks itself by default. This prevents
1914)     Tor users from accidentally accessing any of the exit operator's local
1915)     services.

1916)     </p>
1917) 
1918)     <hr>
1919) 

1920)     <a id="WarningsAboutSOCKSandDNSInformationLeaks"></a>

1921)     <h3><a class="anchor" href="#WarningsAboutSOCKSandDNSInformationLeaks">I
1922)     keep seeing these warnings about SOCKS and DNS information leaks.

1923)     Should I worry?</a></h3>
1924)     <p>

1925)     The warning is:

1926)     </p>
1927)     <p>

1928)     Your application (using socks5 on port %d) is giving Tor only an IP
1929)     address. Applications that do DNS resolves themselves may leak
1930)     information. Consider using Socks4A (e.g. via Polipo or socat) instead.

1931)     </p>
1932)     <p>

1933)     If you are running Tor to get anonymity, and you are worried about an
1934)     attacker who is even slightly clever, then yes, you should worry. Here's why.

1935)     </p>
1936)     <p>

1937)     <b>The Problem.</b> When your applications connect to servers on the
1938)     Internet, they need to resolve hostnames that you can read (like
1939)     www.torproject.org) into IP addresses that the Internet can use (like
1940)     209.237.230.66). To do this, your application sends a request to a DNS
1941)     server, telling it the hostname it wants to resolve. The DNS server
1942)     replies by telling your application the IP address.

1943)     </p>
1944)     <p>

1945)     Clearly, this is a bad idea if you plan to connect to the remote host
1946)     anonymously: when your application sends the request to the DNS server,
1947)     the DNS server (and anybody else who might be watching) can see what
1948)     hostname you are asking for. Even if your application then uses Tor to
1949)     connect to the IP anonymously, it will be pretty obvious that the user
1950)     making the anonymous connection is probably the same person who made
1951)     the DNS request.

1952)     </p>
1953)     <p>

1954)     <b>Where SOCKS comes in.</b> Your application uses the SOCKS protocol
1955)     to connect to your local Tor client. There are 3 versions of SOCKS you
1956)     are likely to run into: SOCKS 4 (which only uses IP addresses), SOCKS 5
1957)     (which usually uses IP addresses in practice), and SOCKS 4a (which uses
1958)     hostnames).

1959)     </p>
1960)     <p>

1961)     When your application uses SOCKS 4 or SOCKS 5 to give Tor an IP address,
1962)     Tor guesses that it 'probably' got the IP address non-anonymously from a
1963)     DNS server. That's why it gives you a warning message: you probably aren't
1964)     as anonymous as you think.

1965)     </p>
1966)     <p>

1967)     <b>So what can I do?</b> We describe a few solutions below.

1968)     </p>
1969)     <ul>
1970)     <li>If your application speaks SOCKS 4a, use it. </li>

1971)     <li>If you only need one or two hosts, or you are good at programming,
1972)     you may be able to get a socks-based port-forwarder like socat to work
1973)     for you; see <a
1974)     href="https://trac.torproject.org/projects/tor/wiki/doc/TorifyHOWTO">the

1975)     Torify HOWTO</a> for examples. </li>

1976)     <li>Tor ships with a program called tor-resolve that can use the Tor
1977)     network to look up hostnames remotely; if you resolve hostnames to IPs
1978)     with tor-resolve, then pass the IPs to your applications, you'll be fine.

1979)     (Tor will still give the warning, but now you know what it means.) </li>
1980) <!-- I'm not sure if this project is still maintained or not
1981) 
1982) <li>You can use TorDNS as a local DNS server to rectify the DNS leakage. See the Torify HOWTO for info on how to run particular applications anonymously. </li>
1983) !-->
1984)     </ul>

1985)     <p>If you think that you applied one of the solutions properly but still
1986)     experience DNS leaks please verify there is no third-party application
1987)     using DNS independently of Tor. Please see <a
1988)     href="#AmITotallyAnonymous">the FAQ entry on whether you're really
1989)     absolutely anonymous using Tor</a> for some examples.

1990)     </p>
1991) 
1992)     <hr>
1993) 

1994)     <a id="SocksAndDNS"></a>

1995)     <h3><a class="anchor" href="#SocksAndDNS">How do I check if my application that uses

1996)     SOCKS is leaking DNS requests?</a></h3>
1997) 
1998)     <p>