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13 <td width="30%" align=right>$Date: 2000/02/18 03:49:20 $
16 <H1>Frequently Asked Questions About Fetchmail</H1>
18 Before reporting any bug, please read <a href="#G3">G3</a> for advice
19 on how to include diagnostic information that will get your bug fixed
20 as quickly as possible. <p>
22 If you have a question or answer you think ought to be added to this FAQ list,
23 mail it to fetchmail's maintainer, Eric S. Raymond, at
24 <A HREF="mailto:esr@thyrsus.com">esr@snark.thyrsus.com</A>.<p>
26 <h1>General questions:</h1>
28 <a href="#G1">G1. What is fetchmail and why should I bother?</a><br>
29 <a href="#G2">G2. Where do I find the latest FAQ and fetchmail sources?</a><br>
30 <a href="#G3">G3. I think I've found a bug. Will you fix it?</a><br>
31 <a href="#G4">G4. I have this idea for a neat feature. Will you add it?</a><br>
32 <a href="#G5">G5. Is there a mailing list for exchanging tips?</a><br>
33 <a href="#G6">G6. So, what's this I hear about a fetchmail paper?</a><br>
34 <a href="#G7">G7. What is the best server to use with fetchmail?</a><br>
35 <a href="#G8">G8. What is the best mail program to use with fetchmail?</a><br>
36 <a href="#G9">G9. How can I avoid sending my password en clair?</a><br>
37 <a href="#G10">G10. Is any special configuration needed to use a dynamic
39 <a href="#G11">G11. Is any special configuration needed to use firewalls?</a><br>
40 <a href="#G12">G12. Is any special configuration needed to <em>send</em> mail?</a><br>
41 <a href="#G13">G13. Is fetchmail Y2K-compliant?</a><br>
42 <a href="#G14">G14. Is there a way in fetchmail to support disconnected IMAP mode?</a><br>
44 <h1>Build-time problems:</h1>
46 <a href="#B1">B1. Lex bombs out while building the fetchmail lexer.</a><br>
47 <a href="#B2">B2. I get link failures when I try to build fetchmail.</a><br>
49 <h1>Fetchmail configuration file grammar questions:</h1>
51 <a href="#F1">F1. Why does my old .fetchmailrc no longer work?</a><br>
52 <a href="#F2">F2. The .fetchmailrc parser won't accept my all-numeric user name.</a><br>
53 <a href="#F3">F3. The .fetchmailrc parser won't accept my host or username beginning with `no'.</a><br>
54 <a href="#F4">F4. I'm migrating from popclient. How do I need to modify my .poprc?</a><br>
55 <a href="#F5">F5. I'm getting a `parse error' message I don't understand.</a><br>
57 <h1>Configuration questions:</h1>
59 <a href="#C1">C1. Why do I need a .fetchmailrc when running as root on my own machine?</a><br>
60 <a href="#C2">C2. How can I arrange for a fetchmail daemon to get killed when I log out?</a><br>
61 <a href="#C3">C3. How do I know what interface and address to use with --interface?</a><br>
62 <a href="#C4">C4. How can I set up support for sendmail's anti-spam features?</a><br>
63 <a href="#C5">C5. How can I poll some of my mailboxes more/less often than others?</a><br>
64 <a href="#C6">C6. Fetchmail works OK started up manually, but not from an init script.</a><br>
66 <h1>How to make fetchmail play nice with various MTAs:</h1>
68 <a href="#T1">T1. How can I use fetchmail with sendmail?</a><br>
69 <a href="#T2">T2. How can I use fetchmail with qmail?</a><br>
70 <a href="#T3">T3. How can I use fetchmail with exim?</a><br>
71 <a href="#T4">T4. How can I use fetchmail with smail?</a><br>
72 <a href="#T5">T5. How can I use fetchmail with SCO's MMDF?</a><br>
73 <a href="#T6">T6. How can I use fetchmail with Lotus Notes?</a><br>
75 <h1>How to make fetchmail work with various servers:</h1>
77 <a href="#S1">S1. How can I use fetchmail with qpopper?</a><br>
78 <a href="#S2">S2. How can I use fetchmail with Microsoft Exchange?</a><br>
79 <a href="#S3">S3. How can I use fetchmail with Compuserve RPA?</a><br>
80 <a href="#S4">S4. How can I use fetchmail with Demon Internet's SDPS?</a><br>
81 <a href="#S5">S5. How can I use fetchmail with usa.net's servers?</a><br>
82 <a href="#S6">S6. How can I use fetchmail with HP OpenMail?</a><br>
83 <a href="#S7">S7. How can I use fetchmail with geocities POP3 servers?</a><br>
84 <a href="#S8">S8. How can I use fetchmail with Hotmail?</a><br>
85 <a href="#S9">S9. How can I use fetchmail with MSN?</a><br>
86 <a href="#S10">S10. How can I use fetchmail with SpryNet?</a><br>
87 <a href="#S11">S11. How can I use fetchmail with FTGate?</a><br>
88 <a href="#S12">S12. How can I use fetchmail with MailMax?</a><br>
89 <a href="#S13">S13. How can I use fetchmail with Novell GroupWise?</a><br>
90 <a href="#S14">S14. How can I use fetchmail with InterChange?</a><br>
92 <h1>How to set up well-known security and authentication methods:</h1>
94 <a href="#K1">K1. How can I use fetchmail with SOCKS?</a><br>
95 <a href="#K2">K2. How can I use fetchmail with IPv6 and IPsec?</a><br>
96 <a href="#K3">K3. How can I get fetchmail to work with ssh?</a><br>
97 <a href="#K4">K4. What do I have to do to use the IMAP-GSS protocol?</a><br>
98 <a href="#K5">K5. How can I use fetchmail with SSL?</a><br>
100 <h1>Runtime fatal errors:</h1>
102 <a href="#R1">R1. Fetchmail isn't working, and -v shows `SMTP connect failed' messages.</a><br>
103 <a href="#R2">R2. When I try to configure an MDA, fetchmail doesn't work.</a><br>
104 <a href="#R3">R3. Fetchmail dumps core when given an invalid rc file.</a><br>
105 <a href="#R4">R4. Fetchmail dumps core in -V mode, but operates normally otherwise.</a><br>
106 <a href="#R5">R5. Running fetchmail in daemon mode doesn't work.</a><br>
107 <a href="#R6">R6. Fetchmail hangs when used with pppd.</a><br>
108 <a href="#R7">R7. Fetchmail randomly dies with socket errors.</a><br>
109 <a href="#R8">R8. Fetchmail running as root stopped working after an OS upgrade</a><br>
110 <a href="#R9">R9. Fetchmail is timing out after fetching certain
111 messages but before deleting them</a><br>
112 <a href="#R10">R10. Fetchmail is timing out during message fetches</a></br>
114 <h1>Disappearing mail</h1>
116 <a href="#D1">D1. I think I've set up fetchmail correctly, but I'm not getting any mail.</a><br>
117 <a href="#D2">D2. All my mail seems to disappear after a dropped connection.</a><br>
118 <a href="#D3">D3. Mail that was being fetched when I interrupted my fetchmail seems to have been vanished.</a><br>
120 <h1>Multidrop-mode problems:</h1>
122 <a href="#M1">M1. I've declared local names, but all my multidrop mail is going to root anyway.</a><br>
123 <a href="#M2">M2. I can't seem to get fetchmail to route to a local domain properly.</a><br>
124 <a href="#M3">M3. I tried to run a mailing list using multidrop, and I have a mail loop!</a><br>
125 <a href="#M4">M4. My multidrop fetchmail seems to be having DNS problems.</a><br>
126 <a href="#M5">M5. I'm seeing long DNS delays before each message is processed.</a><br>
127 <a href="#M6">M6. How do I get multidrop mode to work with majordomo?</a><br>
128 <a href="#M7">M7. Multidrop mode isn't parsing envelope addresses from
129 my Received headers as it should.</a><br>
130 <a href="#M8">M8. Users are getting multiple copies of messages.</a><br>
132 <h1>Mangled mail:</h1>
134 <a href="#X1">X1. Spurious blank lines are appearing in the headers of fetched mail.</a><br>
135 <a href="#X2">X2. My mail client can't see a Subject line.</a><br>
136 <a href="#X3">X3. Messages containing "From" at start of line are being split.</a><br>
137 <a href="#X4">X4. My mail is being mangled in a new and different way.</a><br>
138 <a href="#X5">X5. Using POP3, retrievals seems to be fetching too much!</a><br>
140 <h1>Other problems:</h1>
142 <a href="#O1">O1. The --logfile option doesn't work if the logfile doesn't exist.</a><br>
143 <a href="#O2">O2. Every time I get a POP or IMAP message the header is
144 dumped to all my terminal sessions.</a><br>
145 <a href="#O3">O3. Does fetchmail reread its rc file every poll cycle?</a><br>
146 <a href="#O4">O4. Why do deleted messages show up again when I take
147 a line hit while downloading?</a><br>
148 <a href="#O5">O5. Why is fetched mail being logged with my name, not the real From address?</a><br>
149 <a href="#O6">O6. I'm seeing long sendmail delays or hangs near the start of each poll cycle.</a><br>
150 <a href="#O7">O7. Why doesn't fetchmail deliver mail in date-sorted order?</a><br>
151 <a href="#O8">O8. I'm using pppd. Why isn't my monitor option working?</a><br>
152 <a href="#O9">O9. Why does fetchmail keep retrieving the same messages
153 over and over?</a><br>
157 <h2><a name="G1">G1. What is fetchmail and why should I bother?</a></h2>
159 Fetchmail is a one-stop solution to the remote mail retrieval problem
160 for Unix machines, quite useful to anyone with an intermittent PPP or
161 SLIP connection to a remote mailserver. It can collect mail using any
162 variant of POP or IMAP and forwards via port 25 to the local SMTP
163 listener, enabling all the normal forwarding/filtering/aliasing
164 mechanisms that would apply to local mail or mail arriving via a
165 full-time TCP/IP connection.<p>
167 Fetchmail is not a toy or a coder's learning exercise, but an
168 industrial-strength tool capable of transparently handling every
169 retrieval demand from those of a simple single-user ISP connection up
170 to mail retrieval and rerouting for an entire client domain.
171 Fetchmail is easy to configure, unobtrusive in operation, powerful,
172 feature-rich, and well documented. <P>
174 Fetchmail is <a href="http://www.opensource.org">Open Source</a>
175 software. The openness of the sources is the strongest assurance of
176 quality you can have. Extensive peer review by a large,
177 multi-platform user community has shown that fetchmail is as near
178 bulletproof as the underlying protocols permit.<p>
180 Fetchmail is licensed under the <a
181 href="http://gnu.org//copyleft/gpl.html">GNU General Public
184 If you found this FAQ in the distribution, see the README for fetchmail's
185 full feature list.<p>
188 <h2><a name="G2">G2. Where do I find the latest FAQ and fetchmail
191 The latest HTML FAQ is available alongside the latest fetchmail
192 sources at the fetchmail home page:
193 <a href="http://www.tuxedo.org/~esr/fetchmail">
194 http://www.tuxedo.org/~esr/fetchmail</a>. You can also usually find
196 href="http://sunsite.unc.edu/pub/Linux/system/mail/pop/!INDEX.html">POP
197 mail tools directory on Sunsite</a>.<p>
199 A text dump of this FAQ is included in the fetchmail
200 distribution. Because it freezes at distribution release time, it may
201 not be completely current.<p>
204 <h2><a name="G3">G3. I think I've found a bug. Will you fix it?</a></h2>
206 Yes I will, provided you include enough diagnostic information for me
207 to go on. Send bugs to <a
208 href="mailto:fetchmail-friends@ccil.org">fetchmail-friends</a>. When reporting
209 bugs, please include the following:
212 <li>Your operating system and compiler version.
213 <li>A copy of your POP or IMAP server's greeting line.
214 <li>The name and version of the SMTP listener or MDA you are forwarding to.
215 <li>Any command-line options you used.
216 <li>The output of fetchmail -V called with whatever other
217 command-line options you used.
220 If you have FTP access to your remote mail account, and you have any
221 suspicion that the bug was triggered by a particular message, please
222 include a copy of the message that triggered the bug.<p>
224 Often, the first thing I will do when you report a bug is tell you to
225 upgrade to the newest version of fetchmail, and then see if the
226 problem reproduces. So you'll probably save us both time if you
227 upgrade and test with the latest version <em>before</em> sending in a
230 It is helpful if you include your .fetchmailrc file, but not necessary
231 unless your symptom seems to involve an error in configuration
232 parsing. If you do send in your .fetchmailrc, mask the passwords
235 If fetchmail seems to run and fetch mail, but the headers look mangled
236 (that is, headers are missing or blank lines are inserted in the
237 headers) then read the FAQ items in section <a href="#X1">X</a>
238 before submitting a bug report. Pay special attention to the item on
239 <a href="#generic_mangling">diagnosing mail mangling</a>. There are
240 lots of ways for other programs in the mail chain to screw up that
241 look like fetchmail's fault, but you may be able to fix these by
242 tweaking your configuration.<P>
244 A transcript of the failed session with -v -v (yes, that's
245 <em>two</em> -v options, enabling debug mode) will almost always be useful.
246 It is very important that the transcript include your POP/IMAP server's
247 greeting line, so I can identify it in case of server problems. This
248 transcript will not reveal your passwords, which are specially masked
249 out precisely so the transcript can be passed around.<P>
251 If the bug involves a core dump or hang, a gdb stack trace is good to have.
252 (Bear in mind that you can attach gdb to a running but hung process by
253 giving the process ID as a second argument.) You will need to
257 CFLAGS=-g LDFLAGS=" " ./configure
260 and then rebuild in order to generate a version that can be gdb-traced.<p>
262 Best of all is a mail file which, when fetched, will reproduce the
263 bug under the latest (current) version.<p>
265 Any bug I can reproduce will usually get fixed very quickly, often
266 within 48 hours. Bugs I can't reproduce are a crapshoot. If the
267 solution isn't obvious when I first look, it may evade me for a long
268 time (or to put it another way, fetchmail is well enough tested that the
269 easy bugs have long since been found). So if you want your bug fixed
270 rapidly, it is not just sufficient but nearly <em>necessary</em> that
271 you give me a way to reproduce it.<p>
274 <h2><a name="G4">G4. I have this idea for a neat feature. Will you add it?</a></h2>
276 Probably not. Most of the feature suggestions I get are for ways to
277 set various kinds of administrative policy or add more spam filtering
278 (the most common one, which I used to get about four million times a week
279 and got <em>really</em> tired of, is for tin-like kill files).<p>
281 You can do spam filtering better with procmail or maildrop on the
282 server side and (if you're the server sysadmin) sendmail.cf domain
283 exclusions. You can do other policy things better with the
284 <CODE>mda</CODE> option and script wrappers around fetchmail. If
285 it's a prime-time-vs.-non-prime-time issue, ask yourself whether a
286 wrapper script called from crontab would do the job.<p>
288 I'm not going to do these; fetchmail's job is transport, not policy, and I
289 refuse to change it from doing one thing well to attempting many things badly.
290 One of my objectives is to keep fetchmail simple so it stays reliable.<p>
292 For reasons fetchmail doesn't have other commonly-requested features
293 (such as password encryption, or multiple concurrent polls from the
294 same instance of fetchmail) see the <a
295 href="http://www.tuxedo.org/fetchmail/design.notes.html">design notes</a>.<p>
297 Fetchmail is a mature project, no longer in constant active
298 development. It is no longer my top project, and I am going to be
299 quite reluctant to add features that might either jeopardize its
300 stability or involve me in large amounts of coding.<p>
302 All that said, if you have a feature idea that really is about a transport
303 problem that can't be handled anywhere but fetchmail, lay it on me. I'm
304 very accommodating about good ideas.<p>
307 <h2><a name="G5">G5. Is there a mailing list for exchanging tips?</a></h2>
309 There is a fetchmail-friends list for people who want to discuss fixes
310 and improvements in fetchmail and help co-develop it. It's at <a
311 href="mailto:fetchmail-friends@thyrsus.com">fetchmail-friends@thyrsus.com</a>.
312 There is also an announcements-only list, <em>fetchmail-announce@thyrsus.com</em>.<P>
314 Both lists are SmartList reflectors; sign up in the usual way with a
315 message containing the word "subscribe" in the subject line sent to
316 <a href="mailto:fetchmail-friends-request@thyrsus.com?subject=subscribe">
317 fetchmail-friends-request@thyrsus.com</a> or
318 <a href="mailto:fetchmail-announce-request@thyrsus.com?subject=subscribe">
319 fetchmail-announce-request@thyrsus.com</a>. (Similarly, "unsubscribe"
320 in the Subject line unsubscribes you, and "help" returns general list help) <p>
323 <h2><a name="G6">G6. So, what's this I hear about a fetchmail paper?</a></h2>
325 The fetchmail development was also a sociological experiment, an
326 extended test to see if my theory about the critical features of the
327 Linux development model is correct.<p>
329 The experiment was a success. I wrote a paper about it titled <a
330 href="http://www.tuxedo.org/~esr/writings/cathedral.html">The
331 Cathedral and the Bazaar</a> which was first presented at Linux
332 Kongress '97 in Bavaria and very well received there. It was also
333 given at Atlanta Linux Expo, Linux Pro '97 in Warsaw, and the first
334 Perl Conference, at UniForum '98, and was the basis of an invited
335 presentation at Usenix '98. The folks at Netscape tell me it helped
337 href="http://www.netscape.com/newsref/pr/newsrelease558.html"> give
338 away the source for Netscape Communicator</a>.<p>
340 If you're reading a non-HTML dump of this FAQ, you can find the paper
341 on the Web with a search for that title.<p>
344 <h2><a name="G7">G7. What is the best server to use with fetchmail?</a></h2>
346 The short answer: IMAP4rev1 running over Unix.<P>
348 Here's a longer answer: <P>
350 Fetchmail will work with any POP, IMAP, or ESMTP/ETRN server that
351 conforms to the relevant RFCs (and even some outright broken ones like
352 <a href="#S2">Microsoft Exchange</a> and <a href="#S12">Novell
353 GroupWise</a>). This doesn't mean it works equally well with all,
354 however. POP2 servers, and POP3 servers without LAST, limit
355 fetchmail's capabilities in various ways described on the manual
358 Most modern Unixes (and effectively all Linux/*BSD systems) come with
359 POP3 support preconfigured (but beware of the horribly broken POP3
360 server mentioned in <a href="#D2">D2</a>). An increasing minority
361 also feature IMAP (you can detect IMAP support by running fetchmail in
362 AUTO mode, or by using the `Probe for supported protocols' function in
363 the fetchmailconf utility).<P>
365 If you have the option, we recommend using or installing an IMAP4rev1
366 server; it has the best facilities for tracking message `seen' states.
367 It also recovers from interrupted connections more gracefully than
368 POP3, and enables some significant performance optimizations.<P>
370 Don't be fooled by NT/Exchange propaganda. M$ Exchange is just plain
371 broken (see item <a href="#S2">S2</a>) and NT cannot handle the
372 sustained load of a high-volume remote mail server. Even Microsoft
373 itself knows better than to try this; their own Hotmail service runs
374 over Solaris! For extended discussion, see John Kirch's excellent <a
375 href="http://unix-vs-nt.org/kirch/">white paper</a> on Unix
376 vs. NT performance.<P>
378 You can find sources for IMAP software at <a
379 href="http://www.imap.org">The IMAP Connection</a>; we like the
380 open-source <a href="ftp://ftp.cac.washington.edu/imap/">UW IMAP</a>
381 server, which is the reference implementation of IMAP. UW IMAP's
382 support for GSSAPI gives you a good way to authenticate without
383 sending a password en clair.<P>
385 Source for a high-quality supported implementation of POP is available
386 from the <a href="ftp://ftp.qualcomm.com/eudora/servers/unix/popper/">Eudora
387 FTP site</a>. Don't use 2.5, which has a rather restrictive license.
388 The 2.5.2 version appears to restore the open-source license of
389 previous versions.<P>
392 <h2><a name="G8">G8. What is the best mail program to use with fetchmail?</a></h2>
394 Fetchmail will work with all popular <a href="#T1">mail transport programs</a>.
395 It also doesn't care which user agent you use, and user agents are as a
396 rule almost equally indifferent to how mail is delivered into your system
397 mailbox. So any of the popular Unix mail agents --
398 <a href="http://www.myxa.com/old/elm.html">elm</a>,
399 <a href="http://www.washington.edu/pine/">pine</a>
400 <a href="http://www.cs.indiana.edu/docproject/mail/mh.html">mh</a>,
401 or <a href="http://www.mutt.org">mutt</a>
402 -- will work fine with fetchmail.<p>
404 All this having been said, I can't resist putting in a discreet plug
405 for <a href="http://www.mutt.org">mutt</a>. My own personal mail
406 setup is sendmail plus fetchmail plus mutt. Mutt's interface is only
407 a little different from that of its now-moribund ancestor elm, but its
408 excellent handling of MIME and PGP put it in a class by itself. You
409 won't need its built-in POP3 support, though; most of the mutt
410 developers will cheerfully admit that fetchmail's is better :-).<p>
413 <h2><a name="G9">G9. How can I avoid sending my password en clair?</a></h2>
415 Depending on what your mail server you are talking to, this ranges
416 from trivial to impossible. It may even be next to useless.<P>
418 Most people use fetchmail over phone wires, which are hard to tap.
419 Anybody with the skill and resources to do this could get into your
420 server mailbox with much less effort by subverting the server host.
421 So if your provider setup is modem wires going straight into a service
422 box, you probably don't need to worry.<P>
424 In general there is little point in trying to secure your fetchmail
425 transaction unless you trust the security of the server host you are
426 retrieving mail from. Your vulnerability is more likely to be an
427 insecure local network on the server end (e.g. to somebody with a TCP/IP
428 packet sniffer intercepting Ethernet traffic between the modem
429 concentrator you dial in to and the mailserver host).<P>
431 Having realized this, you need to ask whether password encryption
432 alone will really address your security exposure. If you think you
433 might be snooped, it's better to use end-to-end encryption on your
434 whole mail stream so none of it can be read. One of the advantages of
435 fetchmail over conventional SMTP-push delivery is that you may be able
436 to arrange this by using ssh(1); see <a href="#K3">K3</a>.<P>
438 If ssh/sshd isn't available, or you find it too complicated for you to
439 set up, password encryption will at least keep a malicious cracker
440 from deleting your mail, and require him to either tap your connection
441 continuously or crack root on the server in order to read it.<P>
443 You can deduce what encryptions your mail server has available
444 by looking at the server greeting line (and, for IMAP, the
445 response to a CAPABILITY query). Do a <code>fetchmail -v</code>
446 to see these, or telnet direct to the server port (110 for POP3, 143 for
449 The facility you are most likely to have available is APOP. This is a
450 POP3 feature supported by many servers (fetchmailconf's autoprobe
451 facility will detect it and tell you if you have it). If you see
452 something in the greeting line that looks like an
453 angle-bracket-enclosed Internet address with a numeric left-hand part,
454 that's an APOP challenge (it will vary each time you log in). You can
455 register a secret on the host (using <code>popauth(8)</code> or some
456 program like it). Specify the secret as your password in your
457 .fetchmailrc; it will be used to encrypt the current challenge, and
458 the encrypted form will be sent back the the server for
461 Alternatively, you may have Kerberos available. This may require you
462 to set up some magic files in your home directory on your client
463 machine, but means you can omit specifying any password at all.<P>
465 Fetchmail supports two different Kerberos schemes. One is a
466 POP3 variant called KPOP; consult the documentation of your mail
467 server to see if you have it (one clue is the string "krb-IV" in the
468 greeting line on port 110). The other is an IMAP facility described
469 by RFC1731. You can tell if this one is present by looking for
470 AUTH=KERBEROS_V4 in the CAPABILITY response.<P>
472 If you are fetching mail from a CompuServe POP3 account, you can use
473 their RPA authentication (which works much like APOP). See <a
474 href="#S3">S3</a> for details. If you are fetching mail from
475 Microsoft Exchange, you will be able to use NTLM.<P>
477 Your POP3 server may have the RFC1938 OTP capability to use one-time
478 passwords (if it doesn't, you can get OTP patches for the 2.2 version
479 of the Qualcomm popper from <a href="#cmetz">Craig Metz</a>). To check
480 this, look for the string "otp-" in the greeting line. If you see it,
481 and your fetchmail was built with OPIE support compiled in (see the
482 distribution INSTALL file), fetchmail will detect it also. When using
483 OTP, you will specify a password but it will not be sent en clair.<P>
485 Sadly, there is at present (September 1999) no OTP or APOP-like
486 facility generally available on IMAP servers. However, there do exist
487 patches which will OTP-enable the University of Washington IMAP
488 daemon, version 4.2-FINAL. We have a report that the GSSAPI support
489 in fetchmail works with the GSSAPI support in the most recent version
490 of UW IMAP. Or you can use <a href="#K5">SSL</a> for complete
491 end-to-end encryption if you have an SSL-enabled mailserver.<P>
493 You can get both POP3 and IMAP OTP patches from <a name="cmetz">Craig
495 href="http://www.inner.net/pub/">http://www.inner.net/pub/</a>.<P>
496 These patches use a SASL authentication method named "X-OTP" because
497 there is not currently a standard way to do this; fetchmail also uses
498 this method, so the two will interoperate happily. They better,
499 because this is how Craig gets his mail ;-)<P>
501 (One important win of OTP is that it's not subject to U.S. export
505 <h2><a name="G10">G10. Is any special configuration needed to use a dynamic IP address?</a></h2>
507 Yes. In order to avoid giving indigestion to certain picky MTAs
508 (notably <a href="#T3">exim</a>), fetchmail always makes the RCPT TO
509 address it feeds the MTA a fully qualified one with a hostname part.
510 Normally it does this by appending @ and "localhost", but when you are
511 using Kerberos or ETRN mode it will append @ and your machine's
512 fully-qualified domain name (FQDN).<P>
514 Appending the FQDN can create problems when fetchmail is running in daemon
515 mode and outlasts the dynamic IP address assignment your client
516 machine had when it started up.<P>
518 Since the new IP address (looked up at RCPT TO interpretation time)
519 doesn't match the original, the most benign possible result is that
520 your MTA thinks it's seeing a relaying attempt and refuses. More
521 frequently, fetchmail will try to connect to a nonexistent host
522 address and time out. Worst case, you could up forwarding your mail
523 to the wrong machine!<P>
525 Use the <code>smtpaddress</code> option to force the appended hostname
526 to one with a (fixed) IP address of 127.0.0.1 in your
527 <code>/etc/hosts</code>. (The name `localhost' will usually work; or
528 you can use the IP address itself).<P>
530 Only one fetchmail option interacts directly with your IP address,
531 `<code>interface</code>'. This option can be used to set the gateway
532 device and restrict the IP address range fetchmail will use. Such a
533 restriction is sometimes useful for security reasons, especially on
534 multihomed sites. See <a href="#C3">C3</a>.<P>
536 I recommend against trying to set up the <code>interface</code> option
537 when initially developing your poll configuration -- it's never
538 necessary to do this just to get a link working. Get the link working
539 first, observe the actual address range you see on connections, and
540 add an <code>interface</code> option (if you need one) later.<P>
542 If you're using a dynamic-IP configuration, one other (non-fetchmail)
543 problem you may run into with outgoing mail is that some sites will
544 bounce your email because the hostname your giving them isn't real
545 (and doesn't match what they get doing a reverse DNS on your
546 dynamically-assigned IP address). If this happens, you need to hack
547 your sendmail so it masquerades as your host. Setting<P>
553 in your <code>sendmail.cf</code> will work, or you can set<P>
556 MASQUERADE_AS(smarthost.here)
559 in the m4 configuration and do a reconfigure. (In both cases, replace
560 <code>smarthost.here</code> with the actual name of your mailhost.)
561 See the <a href="http://www.lege.com/sendmail-FAQ.txt">sendmail
562 FAQ</a> for more details.<P>
565 <h2><a name="G11">G11. Is any special configuration needed to use firewalls?</a></h2>
567 No. You can use fetchmail with SOCKS, the standard tool for
568 indirecting TCP/IP through a firewall. You can find out about SOCKS,
569 and download the SOCKS software including server and client code, at
570 the <a href="http://www.socks.nec.com/">SOCKS distribution
573 The specific recipe for using fetchmail with a firewall is at <a
577 <h2><a name="B1">B1. Lex bombs out while building the fetchmail lexer.</a></h2>
579 In the immortal words of Alan Cox the last time this came up: ``Take
580 the Solaris lex and stick it up the backside of a passing Sun
581 salesman, then install <a
582 href="ftp://prep.ai.mit.edu/ftp/pub/gnu">flex</a> and use that. All
583 will be happier.''<P>
585 I couldn't have put it better myself, and ain't going to try now.<P>
588 <h2><a name="G12">G12. Is any special configuration needed to <em>send</em> mail?</a></h2>
590 A user asks: but how do we send mail out to the POP3 server? Do I need
591 to implement another tool or will fetchmail do this too?<p>
593 Fetchmail only handles the receiving side. The sendmail or other
594 preinstalled MTA on your client machine will handle sending mail
595 automatically; it will ship mail that is submitted while the
596 connection is active, and put mail that is submitted while
597 the connection is inactive into the outgoing queue.<P>
599 Normally, sendmail is also run periodically (every 15 minutes on most
600 Linux systems) in a mode that tries to ship all the mail in the
601 outgoing queue. If you have set up something like pppd to
602 automatically dial out when your kernel is called to open a TCP/IP
603 connection, this will ensure that the mail gets out.<P>
606 <h2><a name="G13">G13. Is fetchmail Y2K-compliant?</a></h2>
608 Fetchmail is fully Y2K-compliant.<P>
610 Fetchmail could theoretically have problems when the 32-bit time_t
611 counters roll over in 2038, but I doubt it. Timestamps aren't used
612 for anything but log entry generation. Anyway, if you aren't running
613 on a 64-bit machine by then, you deserve to lose.<P>
616 <h2><a name="G14">G14. Is there a way in fetchmail to support disconnected IMAP mode?</a></H2>
618 No. Fetchmail is a mail transport agent, best understood as a protocol
619 gateway between POP3/IMAP servers and SMTP. Disconnected operation
620 requires an elaborate interactive client. It's a very different problem.<p>
623 <h2><a name="B2">B2. I get link failures when I try to build fetchmail.</a></h2>
625 If you get errors resembling these<P>
628 mxget.o(.text+0x35): undefined referenceto `__res_search'
629 mxget.o(.text+0x99): undefined reference to`__dn_skipname'
630 mxget.o(.text+0x11c): undefined reference to`__dn_expand'
631 mxget.o(.text+0x187): undefined reference to`__dn_expand'
632 make: *** [fetchmail] Error 1
635 then you must add "-lresolv" to the LOADLIBS line in your Makefile
636 once you have installed the `bind' package.<P>
639 <h2><a name="F1">F1. Why does my old .fetchmailrc file no longer work?</a></h2>
641 <h3>If your file predates 5.1.0</h3>
643 In 5.1.0, the <tt>auth</tt> keyword and option were changed to
646 <h3>If your file predates 4.5.5</h3>
648 If the <code>dns</code> option is on (the default), you may need to
649 make sure that any hostname you specify (for mail hosts or for an SMTP
650 target) is a canonical fully-qualified hostname). In order to avoid
651 DNS overhead and complications, fetchmail no longer tries to derive
652 the fetchmail client machine's canonical DNS name at startup.<P>
654 <h3>If your file predates 4.0.6:</h3>
656 Just after the `<CODE>via</CODE>' option was introduced, I realized
657 that the interactions between the `<CODE>via</CODE>',
658 `<CODE>aka</CODE>', and `<CODE>localdomains</CODE>' options were out
659 of control. Their behavior had become complex and confusing, so much so
660 that I was no longer sure I understood it myself. Users were being
661 unpleasantly surprised.<P>
663 Rather than add more options or crock the code, I re-thought it. The
664 redesign simplified the code and made the options more orthogonal, but
665 may have broken some complex multidrop configurations.
667 Any multidrop configurations that depended on the name just after the
668 `<CODE>poll</CODE>' or `<CODE>skip</CODE>' keyword being still
669 interpreted as a DNS name for address-matching purposes, even in the
670 presence of a `<CODE>via</CODE>' option, will break.<P>
672 It is theoretically possible that other unusual configurations (such
673 as those using a non-FQDN poll name to generate Kerberos IV tickets) might
674 also break; the old behavior was sufficiently murky that we can't be
675 sure. If you think this has happened to you, contact the maintainer.<P>
677 <h3>If your file predates 3.9.5:</h3>
679 The `<code>remote</code>' keyword has been changed to `<code>folder</code>'.
680 If you try to use the old keyword, the parser will utter a warning.<P>
682 <h3>If your file predates 3.9:</h3>
684 It could be because you're using a .fetchmailrc that's written in the
685 old popclient syntax without an explicit `<CODE>username</CODE>'
686 keyword leading the first user entry attached to a server entry.
688 This error can be triggered by having a user option such as `<CODE>keep</CODE>'
689 or `<CODE>fetchall</CODE>' before the first explicit username. For
690 example, if you write<p>
693 poll openmail protocol pop3
694 keep user "Hal DeVore" there is hdevore here
697 the `<CODE>keep</CODE>' option will generate an entire user entry with
698 the default username (the name of fetchmail's invoking user).<p>
700 The popclient compatibility syntax was removed in 4.0. It complicated
701 the configuration file grammar and confused users.<p>
703 <h3>If your file predates 2.8:</h3>
705 The `<CODE>interface</CODE>', `<CODE>monitor</CODE>' and
706 `<CODE>batchlimit</CODE>' options changed after 2.8.<p>
708 They used to be global options with `<CODE>set</CODE>' syntax like the
709 batchlimit and logfile options. Now they're per-server options, like
710 `<CODE>protocol</CODE>'.<p>
712 If you had something like<p>
715 set interface = "sl0/10.0.2.15"
718 in your .fetchmailrc file, simply delete that line and insert
719 `interface sl0/10.0.2.15' in the server options part of your `defaults'
722 Do similarly for any `<CODE>monitor</CODE>' or `<CODE>batchlimit</CODE>' options.<p>
725 <h2><a name="F2">F2. The .fetchmailrc parser won't accept my all-numeric user name.</a></h2>
727 Either upgrade to a post-5.0.5 fetchmail or put string quotes around it. :-)<p>
729 The configuration file parser in older fetchmail versions treated any
730 all-numeric token as a number, which confused it when it was
731 expecting a name. String quoting forces the token's class.<p>
733 The lexical analyzer in 5.0.6 and beyond is smarter and assumes
734 any token following "username" or "password" is a string.
737 <h2><a name="F3">F3. The .fetchmailrc parser won't accept my host or username beginning with `no'.</a></h2>
739 See <a href="#F2">F2</a> You're caught in an unfortunate crack between
740 the newer-style syntax for negated options (`no keep', `no rewrite'
741 etc.) and the older style run-on syntax (`nokeep', `norewrite'
744 Upgrade to a 5.0.6 or later fetchmail, or put string quotes around your
748 <h2><a name="F4">F4. I'm migrating from popclient. How do I need to modify my .poprc?</a></h2>
750 If you have been using popclient (the ancestor of this program)
751 at version 3.0b6 or later, start with this<p>
754 (cd; mv .poprc .fetchmailrc)
757 and do <code>fetchmail -V</code> to see if fetchmail's parser understands
758 your configuration.<p>
760 Be aware that some of popclient's unnecessary options have been
761 removed (see the NOTES file in the distribution for explanation). You
762 can't deliver to a local mail file or to standard output any more, and
763 using an MDA for delivery is discouraged. If you throw those options
764 away, fetchmail will now forward your mail into your system's normal
765 Internet-mail delivery path.<p>
767 Actually, using an MDA is now almost always the wrong thing; the MDA
768 facility has been retained only for people who can't or won't run a
769 sendmail-like SMTP listener on port 25. The default, SMTP forwarding
770 to port 25, is better for at least three major reasons. One: it feeds
771 retrieved POP and IMAP mail into your system's normal delivery path
772 along with local mail and normal Internet mail, so all your normal
773 filtering/aliasing/forwarding setup for local mail works. Two:
774 because the port 25 listener returns a positive acknowledge, fetchmail
775 can be sure you're not going to lose mail to a disk-full or some other
776 resource-exhaustion problem. Three: it means fetchmail doesn't have
777 to know where the system mailboxes are, or futz with file locking
778 (which makes two fewer places for it to potentially mess up).<p>
780 If you used to use <CODE>-mda "procmail -d</CODE>
781 <em><you></em><CODE>"</CODE> or something similar, forward to port
782 25 and do "<CODE>| procmail -d</CODE> <em><you></em><CODE>"</CODE> in
783 your ~/.forward file.<p>
785 As long as your new .fetchmailrc file does not use the removed
786 `localfolder' option or `<CODE>limit</CODE>' (which now takes a
787 maximum byte size rather than a line count), a straight move or copy
788 of your .poprc will often work. (The new run control file syntax also
789 has to be a little stricter about the order of options than the old,
790 in order to support multiple user descriptions per server; thus you
791 may have to rearrange things a bit.)<p>
793 Run control files in the minimal .poprc format (without the `username'
794 token) will trigger a warning. To eliminate this warning, add the
795 `<CODE>username</CODE>' keyword before your first user entry per server (it is
796 already required before second and subsequent user entries per server.<p>
798 In some future version the `<CODE>username</CODE>' keyword will be required.<p>
801 <h2><a name="F5">F5. I'm getting a `parse error' message I don't understand.</a></h2>
803 The most common cause of mysterious parse errors is putting a server
804 option after a user option. Check the manual page; you'll probably
805 find that by moving one or more options closer to the `poll' keyword
806 you can eliminate the problem.<p>
808 Yes, I know these ordering restrictions are hard to understand.
809 Unfortunately, they're necessary in order to allow the `defaults'
813 <h2><a name="C1">C1. Why do I need a .fetchmailrc when running as root on my own machine?</a></h2>
815 Ian T. Zimmerman <itz@rahul.net> asked:<p>
817 On the machine where I'm the only real user, I run fetchmail as root
818 from a cron job, like this:<p>
821 fetchmail -u "itz" -p POP3 -s bolero.rahul.net
824 This used to work as is (with no .fetchmailrc file in root's home
825 directory) with the last version I had (1.7 or 1.8, I don't
826 remember). But with 2.0, it RECPs all mail to the local root user,
827 unless I create a .fetchmailrc in root's home directory containing:<p>
830 skip bolero.rahul.net proto POP3
834 It won't work if the second line is just "<CODE>user itz</CODE>". This is silly.<p>
836 It seems fetchmail decides to RECP the `default local user' (i.e. the
837 uid running fetchmail) unless there are local aliases, and the
838 `default' aliases (itz->itz) don't count. They should.<p>
842 No they shouldn't. I thought about this for a while, and I don't much
843 like the conclusion I reached, but it's unavoidable. The problem is
844 that fetchmail has no way to know, in general, that a local user `itz'
847 "Ah!" you say, "Why doesn't it check the password file to see if the remote
848 name matches a local one?" Well, there are two reasons.<p>
850 One: it's not always possible. Suppose you have an SMTP host declared
851 that's not the machine fetchmail is running on? You lose.<p>
853 Two: How do you know server itz and SMTP-host itz are the same person?
854 They might not be, and fetchmail shouldn't assume they are unless
855 local-itz can explicitly produce credentials to prove it (that is, the
856 server-itz password in local-itz's .fetchmailrc file.).<p>
858 Once you start running down possible failure modes and thinking about
859 ways to tinker with the mapping rules, you'll quickly find that all the
860 alternatives to the present default are worse or unacceptably
861 more complicated or both.<p>
864 <h2><a name="C2">C2. How can I arrange for a fetchmail daemon to get killed when I log out?</a></h2>
866 The easiest way to dispatch fetchmail on logout (which will work
867 reliably only if you have just one login going at any time) is to
868 arrange for the command `fetchmail -q' to be called on logout. Under
869 bash, you can arrange this by putting `fetchmail -q' in the file
870 `~/.bash_logout'. Most csh variants execute `~/.logout' on logout.
871 For other shells, consult your shell manual page.<p>
873 Automatic startup/shutdown of fetchmail is a little harder to arrange
874 if you may have multiple login sessions going. In the contrib
875 subdirectory of the fetchmail distribution there is some shell code
876 you can add to your .bash_login and .bash_logout profiles that will
877 accomplish this. Thank James Laferriere <babydr@nwrain.net> for
880 Some people start up and shut down fetchmail using the ppp-up and
881 ppp-down scripts of pppd.<p>
884 <h2><a name="C3">C3. How do I know what interface and address to use with --interface?</a></h2>
886 This depends a lot on your local networking configuration (and right
887 now you can't use it at all except under Linux). However, here are
888 some important rules of thumb that can help. If they don't work, ask
889 your local sysop or your Internet provider.<p>
891 First, you may not need to use --interface at all. If your machine
892 only ever does SLIP or PPP to one provider, it's almost certainly by a
893 point to point modem connection to your provider's local subnet that's
894 pretty secure against snooping (unless someone can tap your phone or
895 the provider's local subnet!). Under these circumstances, specifying
896 an interface address is fairly pointless.<p>
898 What the option is really for is sites that use more than one
899 provider. Under these circumstances, typically one of your provider
900 IP addresses is your mailserver (reachable fairly securely via the
901 modem and provider's subnet) but the others might ship your packets
902 (including your password) over unknown portions of the general
903 Internet that could be vulnerable to snooping. What you'll use
904 --interface for is to make sure your password only goes over the
907 To determine the device:<p>
910 <li> If you're using a SLIP link, the correct device is probably sl0.
911 <li> If you're using a PPP link, the correct device is probably ppp0.
912 <li> If you're using a direct connection over a local network such as
913 an ethernet, use the command `netstat -r' to look at your routing table.
914 Try to match your mailserver name to a destination entry; if you don't
915 see it in the first column, use the `default' entry. The device name
916 will be in the rightmost column.
919 To determine the address and netmask:<p>
922 <li> If you're talking to slirp, the correct address is probably 10.0.2.15,
923 with no netmask specified. (It's possible to configure slirp to present
924 other addresses, but that's the default.)
926 <li> If you have a static IP address, run `ifconfig <device>', where <device>
927 is whichever one you've determined. Use the IP address given after
928 "inet addr:". That is the IP address for your end of the link, and is
929 what you need. You won't need to specify a netmask.
931 <li> If you have a dynamic IP address, your connection IP will vary randomly
932 over some given range (that is, some number of the least significant bits
933 change from connection to connection). You need to declare an address
934 with the variable bits zero and a complementary netmask that sets
938 To illustrate the rule for dynamic IP addresses, let's suppose you're
939 hooked up via SLIP and your IP provider tells you that the dynamic
940 address pool is 255 addresses ranging from 205.164.136.1 to
941 205.164.136.255. Then<p>
944 interface "sl0/205.164.136.0/255.255.255.0"
947 would work. To range over any value of the last two octets
948 (65536 addresses) you would use<p>
951 interface "sl0/205.164.0.0/255.255.0.0"
955 <h2><a name="C4">C4. How can I set up support for sendmail's anti-spam features?</a></h2>
957 This answer covers versions of sendmail from 8.8.7 (the version
958 installed in Red Hat 5.1) upwards. If you have an older version,
959 upgrade to sendmail 8.9.<P>
961 Stock sendmails can now do anti-spam exclusions based on a database of
962 filter rules. The human-readable form of the database is at
963 <tt>/etc/mail/deny</tt>. The database itself is at
964 <tt>/etc/mail/deny.db</tt>.<P>
966 The table itself uses email addresses, domain names, and network
967 numbers as keys. For example,</P>
969 spammer@aol.com REJECT
970 cyberspammer.com REJECT
973 <P>would refuse mail from spammer@aol.com, any user from
974 cyberspammer.com (or any host within the cyberspammer.com domain), and
975 any host on the 192.168.212.* network. (This feature can be used to
976 do other things as well; see the <a
977 href="http://www.sendmail.org/m4/anti-spam.html">sendmail
978 documentation</a> for details)</P>
980 To actually set up the database, run
983 makemap hash deny <deny
987 To test, send a message to your mailing address from that host and
988 then pop off the message with fetchmail, using the -v argument. You
989 can monitor the SMTP transaction, and when the FROM address is parsed,
990 if sendmail sees that it is an address in spamlist, fetchmail will
991 flush and delete it.<p>
993 Under no circumstances put your <strong>mailhost</strong> or <strong>any host
994 you accept mail from</strong> using fetchmail into your reject file. You
995 <strong>will</strong> lose mail if you do this!!!<p>
998 <h2><a name="C5">C5. How can I poll some of my mailboxes more/less
999 often than others?</a></h2>
1001 Use the <cite>interval</cite> keyword on the ones that should be
1002 checked less often. For example, if you do a poll every 5 minutes,
1003 and want to poll some mailboxes every 5 minutes and some every 30
1004 minutes, use something like this:<p>
1007 poll mainsite.example.com proto pop3 user ....
1008 poll secondary.example.com proto pop3 interval 6 user ...
1011 Then secondary.example.com will be polled every 6th time that
1012 mainsite.example.com is polled, which with a polling interval of every
1013 5 minutes means that secondary.example.com will be polled every 30
1017 <h2><a name="C6">Fetchmail works OK started up manually, but not from an init script.</a></h2>
1019 Often, startup scripts have a different environment than an interactive
1020 login shell. For instance, $HOME might point to "/root" when you are
1021 logged in as root, but it might be either unset, or set to "/" when the
1022 startup scripts are running. That means fetchmail at startup can't find
1023 the .fetchmailrc.<p>
1025 Pick a location (such as /etc/fetchmailrc) and use fetchmail's -f
1026 option to point fetchmail at it. That should solve the problem.<p>
1029 <h2><a name="T1">T1. How can I use fetchmail with sendmail?</a></h2>
1031 For most sendmails, no special configuration is required. Eric Allman
1032 tells me that if <code>FEATURE(always_add_domain)</code> is included
1033 in sendmail's configuration, you can leave the <code>rewrite</code>
1036 If your sendmail complains ``sendmail does not relay'', make sure
1037 your sendmail,cf file says
1043 so that sendmail recognizes `localhost' as a name of its host.<p>
1045 If you're mailing from another machine on your local network, also
1046 ensure that its IP address is listed in ip_allow or name in name_allow
1047 (usually in /etc/mail/)<p>
1049 If you find that your sendmail doesn't like the address
1050 `FETCHMAIL-DAEMON@localhost' (which is used in the bouncemail
1051 that fetchmail generates), you may have to set
1052 <code>FEATURE(accept_unqualified_senders)</code>.<P>
1054 Günther Leber reports that Digital Unix sendmails won't work with
1055 fetchmail. The symptom is an error message "<code>553 Local configuration
1056 error, hostname not recognized as local</code>". The problem is that
1057 fetchmail normally feeds sendmail with the client machine's host
1058 address in the MAIL FROM line. These sendmails think this means
1059 they're seeing the result of a mail loop and suppress the mail. You
1060 may be able to work around this by running in <code>--invisible</code> mode.<P>
1062 If you want to support multidrop mode, and you can get access to your
1063 mailserver's sendmail.cf file, it's a good idea to add this rule:<P>
1066 H?l?Delivered-To: $u
1069 and declare `<CODE>envelope "Delivered-To:"</CODE>'. This will cause the
1070 mailserver's sendmail to reliably write the appropriate envelope
1071 address into each message before fetchmail sees it, and tell fetchmail
1072 which header it is. With this change, multidrop mode should work
1073 reliably even when the Received header omits the envelope address
1074 (which will typically be the case when the message has multiple
1077 Martijn Lievart has a more detailed recipe in the contrib subdirectory
1078 of the fetchmail source distribution.
1081 <h2><a name="T2">T2. How can I use fetchmail with qmail?</a></h2>
1083 Turn on the <CODE>forcecr</CODE> option; qmail's listener mode doesn't like
1084 header or message lines terminated with bare linefeeds.<p>
1086 (This information is thanks to Robert de Bath
1087 <robert@mayday.cix.co.uk>.)<p>
1089 If a mailhost is using the qmail package (see <a
1090 href="http://pobox.com/~djb/qmail.html">http://pobox.com/~djb/qmail.html</a>)
1091 then, providing the local hosts are also using qmail, it is possible
1092 to set up one fetchmail link to be reliably collect the mail for an
1095 One of the basic features of qmail is the `Delivered-To:' message
1096 header. Whenever qmail delivers a message to a local mailbox it puts
1097 the username and hostname of the envelope recipient on this line. The
1098 major reason for this is to prevent mail loops. <p>
1100 To set up qmail to batch mail for a disconnected site the ISP-mailhost
1101 will have normally put that site in its `virtualhosts' control file so
1102 it will add a prefix to all mail addresses for this site. This results
1103 in mail sent to 'username@userhost.userdom.dom.com' having a
1104 'Delivered-To:' line of the form:<p>
1107 Delivered-To: mbox-userstr-username@userhost.userdom.dom.com
1110 A single host maildrop will be slightly simpler:
1113 Delivered-To: mbox-userstr-username@userhost.dom.com
1116 The ISP can make the 'mbox-userstr-' prefix anything they choose
1117 but a string matching the user host name is likely.<p>
1119 To use this line you must:<p>
1122 <li>Ensure the option `envelope Delivered-To:' is in the fetchmail
1125 <li>Ensure you have a localdomains containing 'userdom.dom.com' or
1126 `userhost.dom.com' respectively.
1129 So far this reliably delivers messages to the correct machine of the
1130 local network, to deliver to the correct user the 'mbox-userstr-'
1131 prefix must be stripped off of the user name. This can be done by
1132 setting up an alias within the qmail MTA on each local machine.
1133 Simply create a dot-qmail file called '.qmail-mbox-userstr-default'
1134 in the alias directory (normally /var/qmail/alias) with the contents:<p>
1137 | ../bin/qmail-inject -a -f"$SENDER" "${LOCAL#mbox-userstr-}@$HOST"
1140 Note this <em>does</em> require a modern /bin/sh.<p>
1142 Peter Wilson adds: <P>
1144 ``My ISP uses "alias-unzzippedcom-" as the prefix, which means that I
1145 need to name my file ".qmail-unzzippedcom-default". This is due to
1146 qmail's assumption that a message sent to user-xyz is handled by the
1147 file ~user/.qmail-xyz (or ~user/.qmail-default).''<p>
1149 Luca Olivetti adds:<P>
1151 If you aren't using qmail locally, or you don't want to set up the
1152 alias mechanism described above, you can use the option `<code>qvirtual
1153 "mbox-userstr-"</code>' in your fetchmail config file to strip the prefix
1154 from the local user name.<p>
1157 <h2><a name="T3">T3. How can I use fetchmail with exim?</a></h2><p>
1159 If you have <CODE>rewrite</CODE> on: <P>
1161 There is an RFC1123 requirement that MAIL FROM and RCPT TO addresses
1162 you pass to it have to be canonical (e.g. with a fully qualified
1163 hostname part). Therefore fetchmail tries to pass fully qualified
1164 RCPT TO addresses. But exim does not by default accept `localhost' as
1165 a fully qualified domain. This can be fixed.<P>
1167 In exim.conf, add `localhost' to your local_domains declaration if it's not
1168 already present. For example, the author's site at thyrsus.com would
1169 have a line reading:<P>
1172 local_domains = thyrsus.com:localhost
1175 If you have <CODE>rewrite</CODE> off:<P>
1177 MAIL FROM is a potential problem if the MTAs upstream from your fetchmail
1178 don't necessarily pass canonicalized From and Return-Path addresses,
1179 and fetchmail's <CODE>rewrite</CODE> option is off. The specific case
1180 where this has come up involves bounce messages generated by sendmail
1181 on your mailer host, which have the (un-canonicalized) origin address
1184 The right way to fix this is to enable the <CODE>rewrite</CODE> option and
1185 have fetchmail canonicalize From and Return-Path addresses with the
1186 mailserver hostname before exim sees them. This option is enabled by
1187 default, so it won't be off unless you turned it off.<p>
1189 If you must run with <CODE>rewrite</CODE> off, there is a switch in exim's
1190 configuration files that allows it to accept domainless MAIL FROM
1191 addresses; you will have to flip it by putting the line <p>
1194 sender_unqualified_hosts = localhost
1197 in the main section of the exim configuration file. Note that this
1198 will result in such messages having an incorrect domain name attached
1199 to their return address (your SMTP listener's hostname rather than
1200 that of the remote mail server). <p>
1203 <h2><a name="T4">T4. How can I use fetchmail with smail?</a></h2><p>
1205 Smail 3.2 is very nearly plug-compatible with sendmail, and may work
1206 fine out of the box.<P>
1208 We have one report that when processing multiple messages from a
1209 single fetchmail session, smail sometimes delivers them in an
1210 order other than received-date order. This can be annoying because it
1211 scrambles conversational threads. This is not fetchmail's problem,
1212 it is an smail `feature' and has been reported to the maintainers
1215 Very recent smail versions require an <code>-smtp_hello_verify</code>
1216 option in the smail config file. This overrides smail's check to see
1217 that the HELO address is actually that of the client machine, which
1218 is never going to be the case when fetchmail is in the picture.
1219 According to RFC1123 an SMTP listener <em>must</em> allow this
1220 mismatch, so smail's new behavior (introduced sometime between
1221 3.2.0.90 and 3.2.0.95) is a bug.<P>
1224 <h2><a name="T5">T5. How can I use fetchmail with SCO's MMDF?</a></h2><p>
1226 MMDF itself is difficult to configure, but it turns out that
1227 connecting fetchmail to MMDF's SMTP channel isn't that hard.
1229 href="http://www.aplawrence.com/Unixart/uucptofetch.html">
1230 MMDF recipe</a> that describes replacing a UUCP link with
1231 fetchmail feeding MMDF.<P>
1234 <h2><a name="T6">T6. How can I use fetchmail with Lotus Notes?</a></h2><p>
1236 The Lotus Notes SMTP gateway tries to deduce when it should convert \n
1237 to \r\n, but its rules are not the intuitive and correct-for-RFC822
1238 ones. Use `forcecr'.<P>
1241 <h2><a name="S1">S1. How can I use fetchmail with qpopper?</a></h2>
1243 Qualcomm's qpopper is probably the best-of-breed among POP3 servers, and
1244 is very widely deployed. Nevertheless, it has some problems which
1245 fetchmail exposes. We recommend using <a href="#G7">IMAP</a> instead if at
1246 all possible. If you must talk to qpopper, here are some problems to
1249 <h3>Problems with retrieving large messages from qpopper 2.53</h3>
1251 Tony Tang <a href="mailto:tony@atn.com.hk"><tony@atn.com.hk></a>
1252 reports that there is a bad intercation between fetchmail and qpopper
1253 2.5.3 under Red Hat Linux versions 5.0 to 5.2, kernels 2.0.34 to
1254 2.0.35. When fetching very large messages (over 700K) from 2.5.3,
1255 fetchmail will hang with a socket error.<p>
1257 This is probably not a fetchmail bug, but rather a symptom of some
1258 problem in the networking stack that qpopper's transmission pattern is
1259 tickling, as fetchpop (another Linux POP client) also displays the hang
1260 but Netscape running under Win95 does not. The problem can also be
1262 href="http://www.eudora.com/freeware/qpop.html">upgrading to qpopper
1265 <h3>Bad interaction with fetchmail 4.4.2 to 4.4.7</h3>
1267 Versions of fetchmail from 4.4.2 through 4.4.7 had a bad interaction
1268 with Eudora qpopper versions 2.3 and later. See <a href="#X5">X5</a>
1269 for details. The solution is to upgrade your fetchmail.<p>
1272 <h2><a name="S2">S2. How can I use fetchmail with Microsoft Exchange?</a></h2>
1274 Fetchmail now supports the proprietary NTLM mode used with M$ Exchange
1275 servers. To enable this, configure fetchmail with the --enable-NTLM
1276 option and recompile it. Note: if you specify a user option value
1277 that looks like `user@domain', the part to the left of the @ will
1278 be passed as the username and the part to the right as the NTLM domain.<P>
1280 M$ Exchange violates the POP3 RFCs. Its LIST command does not reveal
1281 the real sizes of mail in the pop mailbox, but the sizes of the
1282 compressed versions in the exchange mail database (thanks to Arjan De
1283 Vet and Guido Van Rooij for alerting us to this problem).<P>
1285 Fetchmail works with M$ Exchange, despite this brain damage. Two
1286 features are compromised. One is that the --limit option will not
1287 work right (it will check against compressed and not actual sizes).
1288 The other is that a too-small SIZE argument may be passed to your
1289 ESMTP listener, assuming you're using one (this should not be a
1290 problem unless the actual size of the message is above the listener's
1291 configured length limit).<P>
1293 Somewhat belatedly, I've learned that there's supposed to be a
1294 registry bit that can fix this breakage:<P>
1297 HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MsExchangeIs\Parameters
1298 System\Pop3 Compatibility
1301 This is a bitmask that controls the variations from the standard protocol.
1302 The bits defined are:<P>
1306 <DD>Report exact message sizes for the LIST command
1308 <DD>Allow arbitrary linear whitespace between commands and arguments
1310 <DD>Enable the LAST command
1312 <DD>Allow an empty PASS command (needed for users with blank
1313 passwords, but illegal in the protocol)
1315 <DD>Relax the length restrictions for arguments to commands (protocol
1316 requires 40, but some user names may be longer than that).
1318 <DD>Allow spaces in the argument to the USER command.
1321 There's another one that may be useful to know about:<P>
1324 KEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MsExchangeIs\Parameters
1325 System\Pop3 Performance
1330 <DD>Render messages to a temporary stream instead of sending directly
1331 from the database (should always be on)
1333 Flag unrenderable messages (instead of just failing commands)
1334 (should only be on if you are seeing the problems reported
1337 <DD>Return from the QUIT command before all messages have been deleted.
1340 The Microsoft pod-person who revealed this information to me admitted
1341 that he couldn't find it anywhere in their public knowledge base.<P>
1343 You can mess with these bits. Or, better yet, you can lose that
1344 brain-dead Microsoft crap and install a real operating system on your
1348 <h2><a name="S3">S3. How can I use fetchmail with CompuServe RPA?</a></h2>
1350 First, make sure your fetchmail has the RPA support compiled in.
1351 Stock fetchmail binaries (such as you might get from an RPM) don't.
1352 You can check this by looking at the output of <code>fetchmail -V</code>;
1353 if you see the string "+RPA" after the version ID you're good to go,
1354 otherwise you'll have to build your own from sources (see the INSTALL
1355 file in the source distribution for directions).<P>
1357 Give your CompuServe pass-phrase in lower case as your password. Add
1358 `@compuserve.com' to your user ID so that it looks like `user
1359 <UserID>@compuserve.com', where <UserID> can be either
1360 your numerical userID or your E-mail nickname. An RPA-enabled
1361 fetchmail will automatically check for csi.com in the POP server's
1362 greeting line. If that's found, and your user ID ends with
1363 `@compuserve.com', it will query the server to see if it
1364 is RPA-capable, and if so do an RPA transaction rather than a
1365 plain-text password handshake.<P>
1367 <strong>Warning:</strong> the debug (-v -v) output of fetchmail will show
1368 your pass-phrase in Unicode!<P>
1370 These two .fetchmailrc entries show the difference between an RPA and
1371 non-RPA configuration:
1374 # This version will use RPA
1375 poll csi.com via "pop.site1.csi.com" with proto POP3 and options no dns
1376 user "CSERVE_USER@compuserve.com" there with password "CSERVE_PASSWORD"
1377 is LOCAL_USER here options fetchall stripcr
1379 # This version will not use RPA
1380 poll non-rpa.csi.com via "pop.site1.csi.com" with proto POP3 and options no dns
1381 user "CSERVE_USER" there with password "CSERVE_POP3_PASSWORD"
1382 is LOCAL_USER here options fetchall stripcr
1386 <h2><a name="S4">S4. How can I use fetchmail with Demon Internet's SDPS?</a></h2>
1388 <h3>Single-drop mode</h3>
1390 You can get fetchmail to download the email for just one user from
1391 Demon Internet's POP3 server by giving it a username consisting of your
1392 Demon user name followed by your account name, with an at-sign between
1395 For example, to download email for the user <philh@vision25.demon.co.uk>,
1396 you could use the following .fetchmailrc file:<P>
1399 set postmaster "philh"
1400 poll pop3.demon.co.uk with protocol POP3:
1401 user "philh@vision25" is philh
1404 <h3>Multi-drop mode</h3>
1406 Demon Internet's SDPS service is an implementation of POP3. All messages
1407 have a Received: header added when they enter the maildrop, like this:
1410 Received: from punt-1.mail.demon.net by mailstore for fred@xyz.demon.co.uk
1411 id 899963657:10:27896:0; Thu, 09 Jul 98 05:54:17 GMT
1414 To enable multi-drop mode you need to tell fetchmail that 'mailstore' is
1415 the name of the host which accepted the mail, and let it know the
1416 hostname part(s) of your E-mail address. The following example assumes
1417 that your hostname is xyz.demon.co.uk, and that you have also bought
1418 "mail forwarding" for the domain my-company.co.uk (in which case your
1419 MTA must also be configured to accept mail sent to user@my-company.co.uk)
1422 poll pop3.demon.co.uk proto pop3 aka mailstore no dns:
1423 localdomains xyz.demon.co.uk my-company.co.uk
1424 user xyz is * fetchall
1427 The `fetchall' command ensures that all mail is downloaded. If you
1428 want to leave mail on the server use `uidl' and `keep'; Demon does not
1429 implement the obsolete `top' command, because SDPS combines messages
1430 residing on two separate punt clusters into a single POP3 maildrop.
1431 If you do use UIDL, be aware that the "user@host" form for fetching
1432 mail from a particular Demon host will confuse fetchmail's UIDL code;
1435 Note that Demon may delete mail on the server which is more than 30
1436 days old; see their <a
1437 href="http://www.demon.net/info/helpdesk/demon_products/mail/sdps-tech.shtml">
1438 POP3 page</a> for details.<P>
1440 <h3>The SDPS extension</h3>
1442 There's a different way to do multidrop. It's not necessary on Demon
1443 Internet, since fetchmail can parse Received addresses, but the person
1444 who implemented this didn't know that. It may be useful if Demon
1445 Internet ever changes mail transports.<P>
1447 SDPS includes a non-standard extension for retrieving the envelope of a
1448 message (*ENV), which fetchmail optionally supports if compiled with the
1449 --enable-SDPS option. If you have it, the first line of the fetchmail -V
1450 response will include the string "+SDPS".<P>
1452 Once you have SDPS compiled in, fetchmail in POP3 mode will
1453 automatically detect when it's talking to a Demon Internet host in
1454 multidrop mode, and use the *ENV extension to get an envelope To address.<P>
1456 The autodetection works by looking at the hostname in the POP3
1457 greeting line; if you're accessing Demon Internet through a proxy it
1458 may fail. To force SDPS mode, pick "sdps" as your protocol.<P>
1461 <h2><a name="S5">S5. How can I use fetchmail with usa.net's servers?</a></h2>
1463 Enable `<CODE>fetchall</CODE>'. A user reports that the 2.2 version
1464 of USA.NET's POP server reports that you must use the
1465 `<CODE>fetchall</CODE>' option to make sure that all of the mail is
1466 retrieved, otherwise some may be left on the server. This is almost
1467 certainly a server bug.<P>
1469 The usa.net servers (at least in their 2.2 version, June 1998) don't
1470 handle the TOP command properly, either. Regardless of the argument
1471 you give it, they retrieve only about 10 lines of the message.
1472 Fetchmail normally uses TOP for message retrieval in order to avoid
1473 marking messages seen, but `<CODE>fetchall</CODE>' forces it to use
1476 (Note: Other failure modes have been reported on usa.net's servers.
1477 They seem to be chronically flaky. We recommend finding another
1481 <h2><a name="S6">S6. How can I use fetchmail with HP OpenMail?</a></h2>
1483 No special configuration is required, but OpenMail versions prior to
1484 6.0 have an annoying bug similar to the big one in <a
1485 href="#S2">Microsoft Exchange</a>. The message sizes it gives in the
1486 LIST are rounded to the nearest 1024 bytes. It also has a nasty habit
1487 of discarding headers it doesn't recognize, such as X- and Resent-
1490 As with M$ Exchange, the only real fix for these problems is to get a
1491 POP (or preferably IMAP) server that isn't brain-dead. OpenMail's
1492 project manager claims these bugs have been fixed in 6.0.<P>
1495 <h2><a name="S8">S8. How can I use fetchmail with Hotmail?</a></h2>
1497 You can't, yet. But Hugo Rabson has written a script called `hotmole'
1498 that can retrieve Hotmail mail via the web using Lynx. The script
1500 href="http://www.jin-sei-kai.demon.co.uk/hugo/linux.html">
1501 Hugo Rabson's Linux page</a>, but we're told that project is dead and
1502 the web page seems to be gone.<P>
1505 <h2><a name="S9">S9. How can I use fetchmail with MSN?</a></h2>
1507 You can't. MSN uses something that looks like POP3, except the
1508 authentication part is nonstandard. And of course they don't
1509 document it, so nobody but their Windows clients can speak it.<p>
1511 This is a customer lock-in tactic; we recommend boycotting MSN as the
1512 only appropriate response.<p>
1514 As of 5.0.8, we have support for the client side of NTLM
1515 authentication. It's possible this may enable fetchmail to talk to
1516 MSN; if so, somebody should report it so this FAQ can be corrected.<p>
1519 <h2><a name="S10">S10. How can I use fetchmail with SpryNet?</a></h2>
1521 The SpryNet POP3 servers mark a message queried with TOP as seen.
1522 This means that if your connection drops in mid-message, it may end
1523 up invisibly stuck on your mail spool. Use the <code>fetchall</code>
1524 flag to ensure that it's recovered on the next cycle.<p>
1527 <h2><a name="S11">S11. How can I use fetchmail with FTGate?</a></h2>
1529 The FTGate V2 server (and possibly older versions as well) has a weird
1530 bug. It answers OK twice to a TOP request! Use the
1531 <code>fetchall</code> option to force use of RETR and work around this
1535 <h2><a name="S12">S12. How can I use fetchmail with MailMax?</a></h2>
1537 You can't. At least not if you want to be able to see attachments.
1538 MailMax has a bug; it reports the message length with attachments
1539 but doesn't download them on TOP or RETR. <p>
1542 <h2><a name="S13">S13. How can I use fetchmail with Novell GroupWise?</a></h2>
1544 The Novell GroupWise IMAP server would be better named GroupFoolish;
1545 it is (according to the designer of IMAP) unusably broken. Among
1546 other things, it doesn't include a required content length in its
1547 BODY[TEXT] response.<p>
1549 Fetchmail works around this problem, but we strongly recommend voting
1550 with your dollars for a server that isn't brain-dead. If you stick
1551 with code as shoddy as GroupWise seems to be, you will probably pay
1552 for it with other problems.<p>
1555 <h2><a name="S14">S14. How can I use fetchmail with InterChange?</a></h2>
1557 You can't. At least not if you want to be able to see attachments.
1558 InterChange has a bug similar to the MailMax server; it reports the
1559 message length with attachments but doesn't download them on TOP or
1563 <h2><a name="K1">K1. How can I use fetchmail with SOCKS?</a></h2>
1565 Daniel Sobral <<a href="mailto:dcs@gns.com.br">dcs@gns.com.br</a>
1566 gave us the following recipe:<P>
1569 <LI> Install socks5. You don't need to have a socks server, you just
1570 want the "runsocks" program.
1571 <LI> Set the environment variable SOCKS_SERVER to the server you'll be
1572 using. Alternatively, you may set SOCKS4_SERVER and/or
1573 SOCKS5_SERVER. E.g.:
1575 export SOCKS5_SERVER=socks.my.domain.com
1577 <LI> Set SOCKS5_USER and SOCKS5_PASSWD if needed.
1578 <LI> Run fetchmail through runsocks. Just like this:
1580 runsocks fetchmail [parameters to fetchmail]
1584 It wasn't that hard, was it? :-)<P>
1586 Giuseppe Guerini added a --with-socks option that supports linking
1587 with socks library. If you specify the value of this option as
1588 ``yes'', the configure script will try to find the Rconnect library
1589 and set the makefile up to link it. You can also specify a directory
1590 containing the Rconnect library.<p>
1593 <h2><a name="S7">S7. How can I use fetchmail with geocities POP3 servers?</a></h2>
1595 Nathan Cutler reports that the the mail.geocities.com POP3 servers
1596 fail to include the first Received line of the message in the send to
1597 fetchmail. This can solve problems if your MUA interprets Received
1598 continuations as body lines and doesn't parse any of the following
1601 Workaround is to use "mda" keyword or "-mda" switch:
1603 mda "sed -e '1s/^\t/Received: /' | formail | /usr/bin/procmail -d <user>"
1605 Replace \t with exactly one tabulation character.
1607 You should also consider using "fetchall" option because Geocities' servers
1608 sometimes think that the first 45 messages have already been read.<P>
1610 Fix: Get an email provider that doesn't suck. The pop-up ads on
1611 Geocities are lame, you should boycott them anyway.<P>
1614 <h2><a name="K2">K2. How can I use fetchmail with IPv6 and IPsec?</a></h2>
1616 To use fetchmail with IPv6, you need a system that supports IPv6, the "Basic
1617 Socket Interface Extensions for IPv6" (RFC 2133).
1618 This currently means that you need to have a BSD/OS or NetBSD system with
1619 the NRL IPv6+IPsec software distribution or a Linux system with the latest
1620 experimental kernel and net-tools. It should not be hard to build fetchmail on
1621 other IPv6 implementations if you can port the inet6-apps kit.<P>
1623 To use fetchmail with networking security (read: IPsec), you need a system that
1624 supports IPsec, the API described in the "Network Security API for Sockets"
1625 (draft-metz-net-security-api-01.txt), and the inet6-apps kit. This currently
1626 means that you need to have a BSD/OS or NetBSD system with the NRL IPv6+IPsec
1627 software distribution. A Linux IPsec implementation supporting this API will
1628 probably appear in the coming months.<P>
1630 The NRL IPv6+IPsec software distribution can be obtained from: <a
1631 href="http://web.mit.edu/network/isakmp">http://web.mit.edu/network/isakmp</a>
1634 The inet6-apps kit can be obtained from <a
1635 href="ftp://ftp.ipv6.inner.net/pub/ipv6">ftp://ftp.ipv6.inner.net/pub/ipv6</a>
1636 (via IPv6) or <a href="ftp://ftp.inner.net/pub/ipv6">
1637 ftp://ftp.inner.net/pub/ipv6</a> (via IPv4).<P>
1639 More information on using IPv6 with Linux can be obtained from:
1642 <a href="http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO.html">
1643 http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO.html</a>
1645 <a href="http://www.ipv6.inner.net/ipv6">http://www.ipv6.inner.net/ipv6</a>
1648 <a href="http://www.inner.net/ipv6">http://www.inner.net/ipv6</a> (via IPv4)
1652 <h2><a name="K3">K3. How can I get fetchmail to work with ssh?</a></h2>
1654 We have three recipes for this. The first is easy to set up,
1655 but only supports one user at a time.<P>
1657 First, a lightly edited version of a recipe from Masafumi NAKANE:<p>
1659 1. You must have ssh (the ssh client) on the local host and sshd (ssh
1660 server) on the remote mail server. And you have to configure ssh so
1661 you can login to the sshd server host without a password. (Refer to ssh
1662 man page for several authentication methods.)<p>
1664 2. Add something like following to your .fetchmailrc file: <p>
1667 poll mailhost port 1234 via localhost with proto pop3:
1668 preconnect "ssh -f -L 1234:mailhost:110 mailhost sleep 20
1669 </dev/null >/dev/null; sleep 5";
1672 The sleep is needed on slower machines to prevent fetchmail from
1673 trying to open the socket before ssh actually makes it ready. Faster
1674 machines may not need it.<p>
1676 (Note that 1234 can be an arbitrary port number. Privileged ports can
1677 be specified only by root.) The effect of this ssh command is to
1678 forward connections made to localhost port 1234 (in above example) to
1681 This configuration will enable secure mail transfer. All the
1682 conversation between fetchmail and remote pop server will be
1685 If sshd is not running on the remote mail server, you can specify
1686 intermediate host running it. If you do this, however, communication
1687 between the machine running sshd and the POP server will not be encrypted.
1688 And the preconnect line would be like this:<p>
1691 preconnect "ssh -f -L 1234:mailhost:110 sshdhost sleep 20 </dev/null >/dev/null"
1694 You can work this trick with IMAP too, but the port number 110 in the
1695 above would need to become 143.<p>
1697 Second, a recipe from Charlie Brady <cbrady@ind.tansu.com.au>:<p>
1699 Charlie says: "The [previous] recipe certainly works, but
1700 the solution I post here is better in a few respects":
1703 <LI>this method will not fail if two or more users attempt to use fetchmail
1705 <LI>you are able to use the full facilities of tcpd to control access
1706 <LI>this method does not depend on the preconnect feature of fetchmail, so
1707 can be used for tunneling of other services as well.
1714 Make sure that the "socket" program is installed on the server
1715 machine. Presently it lives at <a
1716 href="ftp://sunsite.unc.edu/pub/linux/system/network/misc/socket-1.1.tar.gz">
1717 ftp://sunsite.unc.edu/pub/linux/system/network/misc/socket-1.1.tar.gz</a>,
1718 but watch out for a change in version number.<P>
1720 Set up an unprivileged account on your system with a .ssh directory
1721 containing an SSH identity file "identity" with no pass phrase,
1722 "identity.pub" and "known_hosts" containing the host key of your
1723 mailhost. Let's call this account "noddy".
1725 On mailhost, set up no-password access for noddy@yourhost. Add to your
1726 SSH authorized_keys file:
1729 command="socket localhost 110",no-port-forwarding 1024 ......
1732 where "<code>1024</code> ......" is the content of noddy's identity.pub file.
1734 Create a script /usr/local/bin/ssh.fm and make it executable:
1738 exec ssh -q -C -l your.login.id -e none mailhost socket localhost 110
1741 Add an entry in inetd.conf for whatever port you choose to use - say:
1744 1234 stream tcp nowait noddy /usr/sbin/tcpd /usr/local/bin/ssh.fm
1747 Send a HUP signal to your inetd.
1750 Now just use localhost:1234 to access your POP server.<P>
1752 For yet a third recipe, see <a href="http://sunsite.unc.edu/LDP/HOWTO/mini/Secure-POP+SSH.html">Secure POP via SSH mini-HOWTO</a>.<P>
1755 <h2><a name="K4">K4. What do I have to do to use the IMAP-GSS protocol?</a></h2>
1757 Fetchmail can use RFC1731 GSSAPI authorization to safely identify you
1758 to your IMAP server, as long as you can share Kerberos V credentials
1759 with your mail host and you have a GSSAPI-capable IMAP server.
1760 UW-IMAP (available via FTP at <a
1761 href="ftp://ftp.cac.washington.edu/mail/">ftp.cac.washington.edu</a>)
1762 is the only one I'm aware of and the one I recommend anyway for other
1763 reasons. You'll need version 4.1-FINAL or greater though, and it has
1764 to have GSS support compiled in.<p>
1766 Neither UW-IMAP nor fetchmail compile in support for GSS by default, since
1767 it requires libraries from the Kerberos V distribution (available via FTP at
1768 <a href="ftp://athena-dist.mit.edu/pub/ATHENA/kerberos">athena-dist.mit.edu</a>
1769 but mind the export restrictions). If you have these, compiling in GSS support
1770 is simple: add a <pre>--with-gssapi=[/path/to/krb5/root]</pre> option to
1771 configure. For instance, I have all of my Kerberos V libraries installed under
1772 /usr/krb5 so I run <pre>configure --with-gssapi=/usr/krb5</pre><p>
1774 Setting up Kerberos V authentication is beyond the scope of this FAQ
1775 (you may find Jim Rome's paper <a
1776 href="http://www.ornl.gov/~jar/HowToKerb.html"> How to Kerberize your
1777 site</a> helpful), but you'll at least need to add a credential for
1778 imap/[mailhost] to the keytab of the mail server (IMAP doesn't just
1779 use the host key). Then you'll need to have your credentials ready on
1780 your machine (cf. kinit).<p>
1782 After that things are very simple. Set your protocol to imap-gss in your
1783 .fetchmailrc, and omit the password, since imap-gss doesn't need one. You
1784 can specify a username if you want, but this is only useful if your mailbox
1785 belongs to a username different from your Kerberos principal. <p>
1787 Now you don't have to worry about your password appearing in cleartext in
1788 your .fetchmailrc, or across the network.<p>
1791 <h2><a name="K5">K5. How can I use fetchmail with SSL?</a></h2>
1793 You'll need to have the <a href="http://www.openssl.org/">OpenSSL</a>
1794 libraries installed. Configure with --with-ssl. If you have the
1795 OpenSSL libraries installed in the default location (/usr/local/ssl)
1796 this will suffice. If you have them installed in a non-default
1797 location, you'll need to specify it as an argument to --with-ssl after
1800 Fetchmail binaries built this way support <code>ssl</code>,
1801 <code>sslkey</code>, and <code>sslcert</code> options that control
1802 SSL encryption. You will need to have an SSL-enabled mailserver
1803 to use these options. See the manual page for detals.<p>
1806 <h2><a name="R1">R1. Fetchmail isn't working, and -v shows `SMTP connect failed' messages.</a></h2>
1808 Fetchmail itself is probably working, but your SMTP port 25 listener
1809 is down or inaccessible.<p>
1811 The first thing to check is if you can telnet to port 25 on your smtp
1812 host (which is normally `localhost' unless you've specified an smtp
1813 option in your .fetchmailrc or on the command line) and get a greeting
1814 line from the listener. If the SMTP host is inaccessible or the listener
1815 is down, fix that first.<p>
1817 If the listener seems to be up when you test with telnet, the most
1818 benign and typical problem is that the listener had a momentary seizure
1819 due to resource exhaustion while fetchmail was polling it -- process
1820 table full or some other problem that stopped the listener process
1821 from forking. If your SMTP host is not `localhost' or something else
1822 in /etc/hosts, the fetchmail glitch could also have been caused by
1823 transient nameserver failure. <p>
1825 Try running fetchmail -v again; if it succeeds, you had one of these
1826 kinds of transient glitch. You can ignore these hiccups, because a
1827 future fetchmail run will get the mail through. <p>
1829 If the listener tests up, but you have chronic failures trying to
1830 connect to it anyway, your problem is more serious. One way to work
1831 around chronic SMTP connect problems is to use --mda. But this only
1832 attacks the symptom; you may have a DNS or TCP routing problem. You
1833 should really try to figure out what's going on underneath before it
1834 bites you some other way. <p>
1836 We have one report (from toby@eskimo.com) that you can sometimes solve
1837 such problems by doing an <CODE>smtp</CODE> declaration with an IP
1838 address that your routing table maps to something other than the
1839 loopback device (he used ppp0).<p>
1841 We also have a report that this error can be caused by having an
1842 /etc/hosts file that associates your client host name with more than
1845 It's also possible that your DNS configuration isn't
1846 looking at <code>/etc/hosts</code> at all. If you're using libc5,
1847 look at <code>/etc/resolv.conf</code>; it should say something like
1853 so your <code>/etc/hosts</code> file is checked first. If you're
1854 running GNU libc6, check your <code>/etc/nsswitch.conf</code> file. Make
1855 sure it says something like
1861 again, in order to make sure <code>/etc/hosts</code> is seen first.<P>
1863 If you have a hostname set for your machine, and this hostname does
1864 not appear in /etc/hosts, you will be able to telnet to port 25 and
1865 even send a mail with rcpt to: user@host-not-in-/etc/hosts, but
1866 fetchmail can't seem to get in touch with sendmail, no matter what you
1867 set smtpaddress to.<p>
1869 We had another report from a Linux user of fetchmail 2.1 who solved his SMTP
1870 connection problem by removing the reference to -lresolv from his link
1871 line and relinking. Apparently in some older Linux distributions the
1872 libc bind library version works better.<p>
1874 As of 2.2, the configure script has been hacked so the bind library is
1875 linked only if it is actually needed. So under Linux it won't be, and
1876 this particular cause should go away.<p>
1879 <h2><a name="R2">R2. When I try to configure an MDA, fetchmail doesn't work.</a></h2>
1881 (I hear this one from people who have run into the blank-line problem in <a href="#X1">X1</a>.)<p>
1883 Try sending yourself test mail and retrieving it using the
1884 command-line options `<CODE>-k -m cat</CODE>'. This will dump exactly what
1885 fetchmail retrieves to standard output (plus the Received line
1886 fetchmail itself adds to the headers). <p>
1888 If the dump doesn't match what shows up in your mailbox when you
1889 configure an MDA, your MDA is mangling the message. If it doesn't
1890 match what you sent, then fetchmail or something on the server is
1894 <h2><a name="R3">R3. Fetchmail dumps core when given an invalid rc file.</a></h2>
1896 This is usually reported from AIX or Ultrix, but has even been known
1897 to happen on Linuxes without a recent version of <code>flex</code>
1898 installed. The problem appears to be a result of building with an
1899 archaic version of lex.<P>
1901 Workaround: fix the syntax of your .fetchmailrc file.<P>
1903 Fix: build and install the latest version of <a
1904 href="ftp://prep.ai.mit.edu/~ftp/pub/gnu">flex</a> from the Free
1905 Software Foundation. An FSF <a
1906 href="http://www.gnu.ai.mit.edu/order/ftp.html">mirror site</a>
1907 will help you get it faster.<P>
1910 <h2><a name="R4">R4. Fetchmail dumps core in -V mode, but operates normally otherwise.</a></h2>
1912 We've had this reported to us under Linux using libc-5.4.17 and gcc-2.7.2.
1913 It does not occur with libc-5.3.12 or earlier versions.<p>
1915 Workaround: link with GNU malloc rather than the stock C library malloc.<p>
1917 We're told there is some problem with the malloc() code in that
1918 version which makes it fragile in the presence of multiple free()
1919 calls on the same pointer (the malloc arena gets corrupted).
1920 Unfortunately it appears from doing gdb traces that whatever free()
1921 calls producing the problem are being made by the C library itself, not the
1922 fetchmail code (they're all from within fclose, and not an fclose called
1923 directly by fetchmail, either).<p>
1926 <h2><a name="R5">R5. Running fetchmail in daemon mode doesn't work.</a><br></h2>
1928 We have one report from a SunOS 4.1.4 user that trying to run
1929 fetchmail in detached daemon mode doesn't work, but that using the
1930 same options with -N (nodetach) is OK.<P>
1932 If this happens, you have a specific portability problem with the code
1933 in daemon.c that detaches and backgrounds the daemon fetchmail. Tell
1934 me about it so I can try to fix it. As a workaround, you can start
1935 fetchmail with -N and an ampersand to background it. A Sun user
1940 (fetchmail --nodetach <other params> &)
1943 The extra pair of parens is significant --- it makes sure that the process
1944 detaches from the initial shell (one more shell is started and dies
1945 immediately, detaching fetchmail and making it child of PID 1). This is
1946 important when you start fetchmail interactively and than quit
1947 interactive shell. The line above makes sure fetchmail lives after
1950 This should not happen under Linux or any truly POSIX-conformant Unix.<P>
1953 <h2><a name="R6">R6. Fetchmail hangs when used with pppd.</a></h2>
1955 Your problem may be with pppd's `demand' option. We have a report that
1956 fetchmail doesn't play well with it, but works with pppd if `demand'
1957 is turned off. We have no idea why this is.<p>
1960 <h2><a name="R7">R7. Fetchmail randomly dies with socket errors.</a></h2>
1962 Check the MTU value in your PPP interface reported by
1963 <code>/sbin/ifconfig</code>. If it's over 600, change it in your PPP
1964 options file. (<code>/etc/ppp/options</code> on my box). Here are
1965 option values that work:<P>
1973 <a name="R8">R8. Fetchmail running as root stopped working after an OS upgrade</a></h2>
1975 In RH 6.0, the HOME value in the boot-time root environment changed
1976 from /root to / as the result of a change in init. Move your
1977 .fetchmailrc or use a -f option to explicitly point at the file.
1978 (Oddly, a similar problem has been reported from Debian systems.)<P>
1981 <h2><a name="R9">R9. Fetchmail is timing out after fetching certain
1982 messages but before deleting them</a></h2>
1984 There's a TCP/IP stalling problem under Redhat 6.0 (and possibly other
1985 recent Linuxes) that can cause this symptom. Brian Boutel writes:<p>
1988 TCP timestamps are turned on on my Linux boxes (I assume it's now the
1989 default). This uses 12 extra bytes per segment.
1990 When the tcp connection starts, the other end agrees a MSS of 1460,
1991 and then fragments 1460 byte chunks into 1448 and 12, because
1992 is is not allowing for the timestamp.<p>
1994 Then, for reasons I can't explain, it waits a long time (typically 2
1995 minutes) after the ack is sent before sending the next (fragmented)
1996 packet. Turning off tcp timestamps avoids the fragmentation and
1997 restores normal behaviour. To do this, [execute]<p>
1999 echo 0 > /proc/sys/net/ipv4/tcp_timestamps<p>
2001 I'm still unclear about the details of why this is happening. At least
2002 [now] I am now getting good performance and no queue blocking.
2006 <h2><a name="R10">R10. Fetchmail is timing out during message fetches</a></h2>
2008 This is probably a general networking issue. Sending a "RETR" command will
2009 cause the server to start sending large amounts of data, which means
2010 large packets. If your networking layer has a packet-fragmentation
2011 problem, that's where you'll see it.<p>
2014 <h2><a name="D1">D1. I think I've set up fetchmail correctly, but I'm not getting any mail.</a></h2>
2016 Maybe you have a .forward or alias set up that you've forgotten about. You
2017 should probably remove it.<p>
2019 Or maybe you're trying to run fetchmail in multidrop mode as root
2020 without a .fetchmailrc file. This doesn't do what you think it
2021 should; see question <a href="#C1">C1</a>.<p>
2023 Or you may not be connecting to the SMTP listener. Run fetchmail -v
2024 and see <a href="#R1">R1</a>.<p>
2027 <h2><a name="D2">D2. All my mail seems to disappear after a dropped connection.</a></h2>
2029 One POP3 daemon used in the Berkeley Unix world that reports itself as
2030 POP3 version 1.004 actually throws the queue away. 1.005 fixed that.
2031 If you're running this one, upgrade immediately. (It also truncates
2032 long lines at column 1024)<P>
2034 Many POP servers, if an interruption occurs, will restore the whole
2035 mail queue after about 10 minutes. Others will restore it right
2036 away. If you have an interruption and don't see it right away, cross
2037 your fingers and wait ten minutes before retrying.<P>
2039 Some servers (such as Microsoft's NTMail) are mis-designed to restore
2040 the entire queue, including messages you have deleted. If you have
2041 one of these and it flakes out on you a lot, try setting a small
2042 <code>--fetchlimit</code> value. This will result in more IP connects
2043 to the server, but will mean it actually executes changes to the queue
2046 Qualcomm's qpopper, used at many BSD Unix sites, is better behaved.
2047 If its connection is dropped, it will first execute all DELE commands as
2048 though you had issued a QUIT (this is a technical violation of
2049 the POP3 RFCs, but a good idea in a world of flaky phone lines). Then it
2050 will re-queue any message that was being downloaded at hangup time.
2051 Still, qpopper may require a noticeable amount of time to do deletions
2052 and clean up its queue. (Fetchmail waits a bit before retrying in
2053 order to avoid a `lock busy' error.)<P>
2056 <h2><a name="D3">D3. Mail that was being fetched when I interrupted my fetchmail seems to have been vanished.</a></h2>
2058 Fetchmail only sends a delete mail request to the server when either
2059 (a) it gets a positive delivery acknowledgment from the SMTP
2060 listener, or (b) it gets an error 571 (the spam-filter error) from the
2061 listener. No interrupt can cause it to lose mail.<p>
2063 However, IMAP2bis has a design problem in that its normal fetch
2064 command marks a message `seen' as soon as the fetch command to get it
2065 is sent down. If for some reason the message isn't actually delivered
2066 (you take a line hit during the download, or your port 25 listener
2067 can't find enough free disk space, or you interrupt the delivery in
2068 mid-message) that `seen' message can lurk invisibly in your server
2071 Workaround: add the `<CODE>fetchall</CODE>' keyword to your fetch options.<p>
2073 Solution: switch to an <a href="http://www.imap.org">IMAP4</a> server.<p>
2076 <h2><a name="M1">M1. I've declared local names, but all my multidrop
2077 mail is going to root anyway.</a></h2>
2079 Somehow your fetchmail is never recognizing the hostname part of
2080 recipient names it parses out of To/Cc/envelope-header lines as
2081 matching the name of the mailserver machine. To check this, run
2082 fetchmail in foreground with -v -v on. You will probably see a lot of
2083 messages with the format ``line rejected, %s is not an alias of the
2084 mailserver'' or ``no address matches; forwarding to %s.'' <p>
2086 These errors usually indicate some kind of DNS configuration problem
2087 either on the server or your client machine. <p>
2089 The easiest workaround is to add a `<CODE>via</CODE>' option (if
2090 necessary) and add enough aka declarations to cover all of your
2091 mailserver's aliases, then say `<CODE>no dns</CODE>'. This will take
2092 DNS out of the picture (though it means mail may be uncollected if
2093 it's sent to an alias of the mailserver that you don't have
2096 It would be better to fix your DNS, however. DNS problems can hurt
2097 you in lots of ways, for example by making your machines
2098 intermittently or permanently unreachable to the rest of the net.<P>
2100 Occasionally these errors indicate the sort of header-parsing problem
2101 described in <a href="#M7">M7</a>.<P>
2104 <h2><a name="M2">M2. I can't seem to get fetchmail to route to a local domain properly.</a></h2>
2106 A lot of people want to use fetchmail as a poor man's internetwork
2107 mail gateway, picking up mail accumulated for a whole domain in a single
2108 server mailbox and then routing based on what's in the To/Cc/Bcc lines.<p>
2110 In general, this is not really a good idea. It would be smarter to
2111 just let the mail sit in the mailserver's queue and use fetchmail's
2112 ETRN mode to trigger SMTP sends periodically (of course, this means
2113 you have to poll more frequently than the mailserver's expiration period).
2114 If you can't arrange this, try setting up a UUCP feed.<P>
2116 If neither of these alternatives is available, multidrop mode may do
2117 (though you <em>are</em> going to get hurt by some mailing list
2118 software; see the caveats under THE USE AND ABUSE OF MULTIDROP
2119 MAILBOXES on the man page). If you want to try it, the way to do it
2120 is with the `<CODE>localdomains</CODE>' option.<p>
2122 In general, if you use localdomains you need to make sure of two other
2125 <strong>1. You've actually set up your .fetchmailrc entry to invoke multidrop mode.</strong><p>
2127 Many people set a `<CODE>localdomains</CODE>' list and then forget
2128 that fetchmail wants to see more than one name (or the wildcard `*')
2129 in a `<CODE>here</CODE>' list before it will do multidrop routing.<p>
2131 <strong>2. You may have to set `no envelope'.</strong><p>
2133 Normally, multidrop mode tries to deduce an envelope address from a message
2134 before parsing the To/Cc/Bcc lines (this enables it to avoid losing to mailing
2135 list software that doesn't put a recipient address in the To lines).<p>
2137 Some ways of accumulating a whole domain's messages in a single server
2138 mailbox mean it all ends up with a single envelope address that is
2139 useless for rerouting purposes. You may have to set `<CODE>no
2140 envelope</CODE>' to prevent fetchmail from being bamboozled by this.<p>
2142 Check also answer <a href="#T1">T1</a> on a reliable way to do multidrop
2143 delivery if your ISP (or your mail redirection provider) is using qmail.<p>
2146 <h2><a name="M3">M3. I tried to run a mailing list using multidrop, and I have a mail loop!</a></h2>
2148 This isn't fetchmail's fault. Check your mailing list. If the list
2149 expansion includes yourself or anybody else at your mailserver (that is, not on
2150 the client side) you've created a mail loop. Just chop the host part off any
2151 local addresses in the list.<p>
2153 If you use sendmail, you can check the list expansion with
2154 <CODE>sendmail -bv</CODE>.<p>
2157 <h2><a name="M4">M4. My multidrop fetchmail seems to be having DNS problems.</a></h2>
2159 We have one report from a Linux user (not the same one as in <a
2160 href="#R1">R1</a>!) who solved this problem by removing the reference
2161 to -lresolv from his link line and relinking. Apparently in some
2162 older Linux distributions the libc5 bind library version works
2165 As of 2.2, the configure script has been hacked so the bind library is linked
2166 only if it is actually needed. So under Linux it won't be, and this problem
2170 <h2><a name="M5">M5. I'm seeing long DNS delays before each message is processed.</a></h2>
2172 Use the `<CODE>aka</CODE>' option to pre-declare as many of your
2173 mailserver's DNS names as you can. When an address's host part
2174 matches an aka name, no DNS lookup needs to be done to check it.<p>
2176 If you're sure you've pre-declared all of your mailserver's DNS names,
2177 you can use the `<CODE>no dns</CODE>' option to prevent other hostname
2178 parts from being looked up at all.<p>
2180 Sometimes delays are unavoidable. Some SMTP listeners try to call DNS
2181 on the From-address hostname as a way of checking that the address is valid.<p>
2184 <h2><a name="M6">M6. How do I get multidrop mode to work with majordomo?</a></h2>
2186 In order for sendmail to execute the command strings in the majordomo
2187 alias file, it is necessary for sendmail to think that the mail it
2188 receives via SMTP really is destined for a local user name. A normal
2189 virtual-domain setup results in delivery to the default mailbox,
2190 rather than expansion through majordomo.<P>
2192 Michael <michael@bizsystems.com> gave us a recipe for dealing
2193 with this case that pairs a run control file like this:<P>
2196 poll your.pop3.server proto pop3:
2198 localdomains virtual.localdomain1.com virtual.localdomain2.com ...
2199 user yourISPusername is root * here,
2200 password yourISPpassword fetchall
2203 with a hack on your local sendmail.cf like this:<P>
2206 #############################################
2207 # virtual info, local hack for ruleset 98 #
2208 #############################################
2210 # domains to treat as direct mapped local domain
2212 CVvirtual.localdomain1.com virtual.localdomain2.com ...
2213 ---------------------------
2215 -------------------------
2216 # handle virtual users
2218 R$+ <@ $=V . > $: $1 < @ $j . >
2219 R< @ > $+ < @ $=V . > $: $1 < @ $j . >
2220 R< @ > $+ $: $1
2221 R< error : $- $+ > $* $#error $@ $1 $: $2
2222 R< $+ > $+ < @ $+ > $: $>97 $1
2225 This ruleset just strips virtual domain names off the addresses of incoming
2226 mail. Your sendmail must be 8.8 or newer for this to work. Michael
2230 I use this scheme with 2 virtual domains and the default ISP
2231 user+domain and service about 30 mail accounts + majordomo on my
2232 inside pop3 server with fetchmail and sendmail 8.83
2236 <h2><a name="M7">M7. Multidrop mode isn't parsing envelope addresses from
2237 my Received headers as it should.</a></h2>
2239 It may happen that you're getting what appear to be well-formed
2240 sendmail Received headers, but fetchmail can't seem to extract an
2241 envelope address from them. There can be a couple of reasons for
2244 <h3>Spurious Received lines need to be skipped:</h3>
2246 First, fetchmail might be looking at the wrong Received header.
2247 Normally it looks only on the first one it sees, on the theory that
2248 that one was last added and is going to be the one containing your
2249 mailserver's theory of who the message was addressed to.<P>
2251 Some (unusual) mailserver configurations will generate extra Received
2252 lines which you need to skip. To arrange this, use the optional
2253 skip prefix argument of the `envelope' option; you may need to say
2254 something like `<code>envelope 1 Received</code>' or `<code>envelope 2
2257 <h3>The `by' clause doesn't contain a mailserver alias:</h3>
2259 When fetchmail parses a Received line that looks like
2262 Received: from send103.yahoomail.com (send103.yahoomail.com [205.180.60.92])
2263 by iserv.ttns.net (8.8.5/8.8.5) with SMTP id RAA10088
2264 for <ksturgeon@fbceg.org>; Wed, 9 Sep 1998 17:01:59 -0700
2267 it checks to see if `iserv.ttns.net' is a DNS alias of your mailserver
2268 before accepting `ksturgeon@fbceg.org' as an envelope address. This
2269 check might fail if your DNS were misconfigured, or if you were using `no dns'
2270 and had failed to declare iserv.ttns.net as an alias of your server.<P>
2273 <h2><a name="M8">M8. Users are getting multiple copies of messages.</a></h2>
2275 It's a consequence of multidrop. What's happening is that you have
2276 N users subscribed to the same list. The list software sends N
2277 copies, not knowing they will end up in the same multidrop box. Since
2278 they are both locally addressed to all N users, fetchmail delivers N
2279 copies to each user.<P>
2281 Fetchmail tries to eliminate adjacent duplicate messages in a
2282 multidrop mailbox. However, this logic depends on the message-ID
2283 being identical in both copies. It also depends on the two copies
2284 being adjacent in the server mailbox. The former is usually the case,
2285 but the latter condition sometimes fails in a timing-dependent way if
2286 the server was processing multiple incoming mail streams.
2288 I could eliminate this problem by keeping a list of all message-IDs
2289 received during a poll so far and dropping any message that matches a
2290 seen mail ID. The touble is that this is an O(N**2) operation that
2291 might significantly slow down the retriweval of large mail batches.<P>
2294 <h2><a name="X1">X1. Spurious blank lines are appearing in the headers of fetched mail.</a></h2>
2296 What's probably happening is that the POP/IMAP daemon on your
2297 mailserver is inserting a non-RFC822 header (like X-POP3-Rcpt:) and
2298 something in your delivery path (most likely an old version of the
2299 <em>deliver</em> program, which sendmail often calls to do local delivery) is
2300 failing to recognize it as a header.<p>
2302 This is not fetchmail's problem. The first thing to try is installing
2303 a current version of <em>deliver</em>. If this doesn't work, try to
2304 figure out which other program in your mail path is inserting the
2305 blank line and replace that. If you can't do either of these things,
2306 pick a different MDA (such as procmail) and declare it with the
2307 `<CODE>mda</CODE>' option.<p>
2310 <h2><a name="X2">X2. My mail client can't see a Subject line.</a></h2>
2312 First, see <a href="#X1">X1</a>. This is quite probably the same
2313 problem (X-POP3-Rcpt header or something similar being inserted by
2314 the server and choked on by an old version of <em>deliver</em>).<p>
2316 The O'Reilly sendmail book does warn that IDA sendmail doesn't process
2317 X- headers correctly. If this is your problem, all I can suggest is
2318 replacing IDA sendmail, because it's broken and not RFC822 conformant.<p>
2321 <h2><a name="X3">X3. Messages containing "From" at start of line are being split.</a></h2>
2323 If you know the messages aren't split in your server mailbox, then this
2324 is a problem with your POP/IMAP server, your client-side SMTP listener or
2325 your local delivery agent. Fetchmail cannot split messages.<p>
2327 Some POP server daemons ignore Content-Length headers and split messages on
2328 From lines. We have one report that the 2.1 version of the BSD popper
2329 program (as distributed on Solaris 2.5 and elsewhere) is broken this way.<p>
2331 You can test this. Declare an mda of `cat' and send yourself one
2332 piece of mail containing "From" at start of a line. If you see a
2333 split message, your POP/IMAP server is at fault. Upgrade to a more
2336 Sendmail and other SMTP listeners don't split RFC822 messages either.
2337 What's probably happening is either sendmail's local delivery agent or
2338 your mail reader are not quite RFC822-conformant and are breaking
2339 messages on what it thinks are Unix-style From headers. You can
2340 figure out which by looking at your client-side mailbox with vi or
2341 more. If the message is already split in your mailbox, your local
2342 delivery agent is the problem. If it's not, your mailreader is the
2345 If you can't replace the offending program, take a look at your
2346 sendmail.cf file. There will likely be a line something like<p>
2349 Mlocal, P=/usr/bin/procmail, F=lsDFMShP, S=10, R=20/40, A=procmail -Y -d $u
2352 describing your local delivery agent. Try inserting the `E' option in the
2353 flags part (the F= string). This will make sendmail turn each dangerous
2354 start-of-line From into a >From, preventing programs further downstream
2358 <h2><a name="generic_mangling"><a name="X4">X4. My mail is being mangled in a new and different way</a></a></h2>
2360 The first thing you need to do is pin down what program is doing the
2361 mangling. We don't like getting bug reports about fetchmail that are
2362 actually due to some other program's malfeasance, so please go through
2363 this diagnostic sequence before sending us a complaint.<P>
2365 There are five possible culprits to consider, listed here in the order
2366 they pass your mail:<P>
2369 <li> Programs upstream of your server mailbox.
2370 <li> The POP or IMAP server on your mailserver host.
2371 <li> The fetchmail program itself.
2372 <li> Your local sendmail.
2373 <li> Your LDA (local delivery agent), as called by sendmail or
2374 specified by <code>mda</CODE>.
2377 Often it happens that fetchmail itself is OK, but using it exposes
2378 pre-existing bugs in your downstream software, or your downstream
2379 software has a bad interaction with POP/IMAP. You need to pin down
2380 exactly where the message is being garbled in order to deduce what is
2381 actually going on.<P>
2383 The first thing to do is send yourself a test message, and retrieve it
2384 with a .fetchmailrc entry containing the following (or by running with
2385 the equivalent command-line options):<P>
2388 mda "cat >MBOX" keep fetchall
2391 This will capture what fetchmail gets from the server, except for (a)
2392 the extra Received header line fetchmail prepends, (b) header address
2393 changes due to <code>rewrite</code>, and (c) any end-of-line changes
2394 due to the <code>forcecr</code> and <code>stripcr</code> options.
2395 MBOX will in fact contain what programs downstream of fetchmail
2398 The most common causes of mangling are bugs and misconfigurations in
2399 those downstream programs. If MBOX looks unmangled, you will know
2400 that is what is going on and that it is not fetchmail's problem. Take
2401 a look at the other FAQ items in this section for possible clues about
2402 how to fix your problem.<P>
2404 If MBOX looks mangled, the next thing to do is compare it with your
2405 actual server mailbox (if possible). That's why you specified
2406 <code>keep</code>, so the server copy would not be deleted. If your
2407 server mailbox looks mangled, programs upstream of your server mailbox
2408 are at fault. Unfortunately there is probably little you can do about
2409 this aside from complaining to your site postmaster, and nothing at
2410 all fetchmail can do about it!<P>
2412 More likely you'll find that the server copy looks OK. In that case
2413 either the POP/IMAP server or fetchmail is doing the mangling. To
2414 determine which, you'll need to telnet to the server port and simulate
2415 a fetchmail session yourself. This is not actually hard (both POP3
2416 and IMAP are simple, text-only, line-oriented protocols) but requires
2417 some attention to detail. You should be able to use a fetchmail -v
2418 log as a model for a session, but remember that the "*" in your LOGIN
2419 or PASS command dump has to be replaced with your actual password.<P>
2421 The objective of manually simulating fetchmail is so you can see
2422 exactly what fetchmail sees. If you see a mangled message, then your
2423 server is at fault, and you probably need to complain to your
2424 mailserver administrators. However, we like to know what the broken
2425 servers are so we can warn people away from them. So please send
2426 us a transcript of the session including the mangling <em>and the
2427 server's initial greeting line</em>. Please tell us anything else
2428 you think might be useful about the server, like the server host's
2429 operating system.<P>
2431 If your manual fetchmail simulation shows an unmangled message,
2432 congratulations. You've found an actual fetchmail bug, which is a
2433 pretty rare thing these days. Complain to us and we'll fix it.
2434 Please include the session transcript of your manual fetchmail
2435 simulation along with the other things described in the FAQ entry on
2436 <a href="#G3">reporting bugs</a>.
2439 <h2><a name="X5">X5. Using POP3, retrievals seems to be fetching too much!</a></h2>
2441 This may happen in versions of fetchmail after 4.4.1 and before 4.4.8.
2442 Versions after 4.4.1 use POP3's TOP command rather than RETR, in order
2443 to avoid marking the message seen (leaving it unseen is helpful for
2444 later recovery if you lose your connection in the middle of a
2447 Versions of fetchmail from 4.4.2 through 4.4.7 had a bad interaction
2448 with Eudora qpopper versions 2.3 and later. The TOP bounds check was
2449 fooled by an overflow condition in the TOP argument. Decrementing the
2450 TOP argument in 4.4.7 fixed this.<P>
2452 Fix: Upgrade to a later version of fetchmail.<P>
2454 Workaround: set the <code>fetchall</code> option. Under POP3 in these
2455 fetchmail version only, this had the side effect of forcing RETR
2459 <h2><a name="O1">O1. The --logfile option doesn't work if the logfile doesn't exist.</a></h2>
2461 This is a feature, not a bug. It's in line with normal practice for
2462 system daemons and allows you to suppress logging by removing the log,
2463 without hacking potentially fragile startup scripts. To get around
2464 it, just touch(1) the logfile before you run fetchmail (this will have
2465 no effect on the contents of the logfile if it already exists).<P>
2468 <h2><a name="O2">O2. Every time I get a POP or IMAP message the header
2469 is dumped to all my terminal sessions.</a></h2>
2471 Fetchmail uses the local sendmail to perform final delivery, which
2472 Netscape and other clients doesn't do; the announcement of new messages
2473 is done by a daemon that sendmail pokes. There should be a ``biff''
2474 command to control this. Type
2480 to turn it off. If this doesn't work, try the command
2486 which is essentially what <code>biff -n</code> will do. If this
2487 doesn't work, comment out any reference to ``comsat'' in your
2488 /etc/inetd.conf file and restart inetd.<P>
2490 In Slackware Linux distributions, the last line in /etc/profile is
2502 to solve the problem system-wide.<P>
2505 <h2><a name="O3">O3. Does fetchmail reread its rc file every poll cycle?</a></h2>
2507 No, but versions 5.2.2 and later will notice when you modify your rc
2508 file and restart, reading it.
2511 <h2><a name="O4">O4. Why do deleted messages show up again when I take
2512 a line hit while downloading?</a></h2>
2514 Because you're using a POP3 other than Qualcomm qpopper, or an IMAP
2515 with a long expunge interval.<P>
2517 According to the POP3 RFCs, deletes aren't actually performed until
2518 you issue the end-of-session QUIT command. Fetchmail cannot fix this,
2519 because doing it right takes cooperation from the server. There are
2520 two possible remedies:<P>
2522 One is to switch to qpopper (the free POP3 server from Qualcomm,
2523 the Eudora people). The qpopper software violates the POP3 RFCs by
2524 doing an expunge (removing deleted messages) on a line hangup, as well
2525 as on processing a QUIT command.<P>
2527 The other (which we recommend) is to switch to <a
2528 href="http://www.imap.org">IMAP</a>. IMAP has an explicit expunge
2529 command and fetchmail normally uses it to delete messages immediately
2530 after they are downloaded.<P>
2532 If you get very unlucky, you might take a line hit in the window
2533 between the delete and the expunge. If you've set a longer expunge
2534 interval, the window gets wider. This problem should correct itself
2535 the next time you complete a successful query.<P>
2538 <h2><a name="O5">O5. Why is fetched mail being logged with my name, not the real From address?</a></h2>
2540 Because logging is done based on the address indicated by the sending
2541 SMTP's MAIL FROM, and some listeners are picky about that address.<p>
2543 Some SMTP listeners get upset if you try to hand them a MAIL FROM
2544 address naming a different host than the originating site for your
2545 connection. This is a feature, not a bug -- it's supposed to help
2546 prevent people from forging mail with a bogus origin site. (RFC 1123
2547 says you shouldn't do this exclusion...)<p>
2549 Since the originating site of a fetchmail delivery connection is
2550 localhost, this effectively means these picky listeners will barf on
2551 any MAIL FROM address fetchmail hands them with an @ in it!<p>
2553 Versions 2.1 and up try the header From address first and fall back to
2554 the calling-user ID. So if your SMTP listener isn't picky, the log
2558 <h2><a name="O6">O6. I'm seeing long sendmail delays or hangs near the start of each poll cycle.</a></h2>
2560 Sendmail does a hostname lookup when it first starts up, and also each
2561 time it gets a HELO in listener mode.<p>
2563 Your resolver configuration may be causing one of these lookups to
2564 fail and time out. Check <code>/etc/resolv.conf</code> and
2565 <code>/etc/hosts</code> file. Make sure your hostname and
2566 fully-qualified domain name are both in <code>/etc/hosts</code>, and
2567 that hosts is looked at before DNS is queried. You probably also want
2568 your remote mail server(s) to be in the hosts file.<p>
2570 You can suppress the startup-time lookup if need to by reconfiguring
2571 with <code>FEATURE(nodns)</code>.<p>
2573 Configuring your bind library to cache DNS lookups locally may help,
2574 and is a good idea for speeding up other services as well. Switching to
2575 a faster MTA like qmail or exim might help. <p>
2578 <h2><a name="O7">O7. Why doesn't fetchmail deliver mail in date-sorted order?</a></h2>
2580 Because that's not the order the server hands it to fetchmail in.<P>
2582 Fetchmail getting mail from a POP server delivers mail in the order
2583 that your server delivers mail. Fetchmail can't do anything about
2584 this; it's a limitation of the underlying POP protocol.<P>
2586 In theory it might be possible for fetchmail in IMAP mode to sort
2587 messages by date, but this would be in violation of two basics of
2588 fetchmail's design philosophy: (a) to be as simple and transparent a
2589 pipe as possible, and (b) to <em>hide</em>, rather than emphasize, the
2590 differences between the remote-fetch protocols it uses.<P>
2592 Re-ordering messages is a user-agent function, anyway.<P>
2595 <h2><a name="O8">O8. I'm using pppd. Why isn't my monitor option working?</a></h2>
2597 There is a combination of circumstances that can confuse fetchmail.
2598 If you have set up demand dialing with pppd, and pppd has an idle
2599 timeout, and you have lcp-echo-interval set, then the
2600 lcp-echo-interval time must be longer than the pppd idle timeout.
2601 Otherwise it is going keep increasing the packet counters that fetchmail
2602 relies upon, triggering fetchmail into polling after its own delay
2603 interval and thus preventing the pppd link from ever reaching its
2604 inactivity timeout.<p>
2607 <h2><a name="O9">O9. Why does fetchmail keep retrieving the same messages
2610 First, check to see that you haven't enabled the <cite>keep</cite>
2611 and <cite>fetchall</cite> option. If you have, turn <cite>keep</cite> off.<p>
2613 This can also happen when some other mail client is logged in to your
2614 mail server, if it uses a simple exclusive-locking scheme (and many,
2615 especially most POP3 servers, do exactly that). Your fetchmail is
2616 able to retrieve the messages, but because the mailbox is write-locked
2617 by the other instance yours can neither mark messages seen or delete them.
2618 The solution is to either (a) wait for the other client to finish, or (b)
2622 <table width="100%" cellpadding=0><tr>
2623 <td width="30%">Back to <a href="index.html">Fetchmail Home Page</a>
2624 <td width="30%" align=center>To <a href="/~esr/sitemap.html">Site Map</a>
2625 <td width="30%" align=right>$Date: 2000/02/18 03:49:20 $
2628 <P><ADDRESS>Eric S. Raymond <A HREF="mailto:esr@thyrsus.com"><esr@snark.thyrsus.com></A></ADDRESS>
2633 compile-command: "(cd ~/WWW; upload fetchmail/fetchmail-FAQ.html)"