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19 <td width="30%" align="right">$Date: 2003/08/06 04:31:10 $</td>
24 <h1>Frequently Asked Questions About Fetchmail</h1>
26 <p>Before reporting any bug, please read <a href="#G3">G3</a> for
27 advice on how to include diagnostic information that will get your
28 bug fixed as quickly as possible.</p>
30 <p>If you have a question or answer you think ought to be added to
31 this FAQ list, mail it to fetchmail's maintainer, Eric S. Raymond,
32 at <a href="mailto:esr@thyrsus.com">esr@thyrsus.com</a>.</p>
34 <h1>General questions:</h1>
36 <a href="#G1">G1. What is fetchmail and why should I bother?</a><br/>
37 <a href="#G2">G2. Where do I find the latest FAQ and fetchmail sources?</a><br/>
38 <a href="#G3">G3. I think I've found a bug. Will you fix it?</a><br/>
39 <a href="#G4">G4. I have this idea for a neat feature. Will you add it?</a><br/>
40 <a href="#G5">G5. I want to make fetchmail behave like Outlook Express.</a><br/>
41 <a href="#G6">G6. Is there a mailing list for exchanging tips?</a><br/>
42 <a href="#G7">G7. So, what's this I hear about a fetchmail paper?</a><br/>
43 <a href="#G8">G8. What is the best server to use with fetchmail?</a><br/>
44 <a href="#G9">G9. What is the best mail program to use with fetchmail?</a><br/>
45 <a href="#G10">G10. How can I avoid sending my password en clair?</a><br/>
46 <a href="#G11">G11. Is any special configuration needed to use a dynamic IP address?</a><br/>
47 <a href="#G12">G12. Is any special configuration needed to use firewalls?</a><br/>
48 <a href="#G13">G13. Is any special configuration needed to <em>send</em> mail?</a><br/>
49 <a href="#G14">G14. Is fetchmail Y2K-compliant?</a><br/>
50 <a href="#G15">G15. Is there a way in fetchmail to support disconnected IMAP mode?</a><br/>
51 <a href="#G16">G16. How will fetchmail perform under heavy loads?</a><br/>
54 <h1>Build-time problems:</h1>
56 <a href="#B1">B1. Make coughs and dies when building on FreeBSD.</a><br/>
57 <a href="#B2">B2. Lex bombs out while building the fetchmail lexer.</a><br/>
58 <a href="#B3">B3. I get link failures when I try to build fetchmail.</a><br/>
59 <a href="#B4">B4. I get build failures in the intl directory.</a><br/>
61 <h1>Fetchmail configuration file grammar questions:</h1>
63 <a href="#F1">F1. Why does my old .fetchmailrc no longer work?</a><br/>
64 <a href="#F2">F2. The .fetchmailrc parser won't accept my all-numeric user name.</a><br/>
65 <a href="#F3">F3. The .fetchmailrc parser won't accept my host or username beginning with `no'.</a><br/>
66 <a href="#F4">F4. I'm getting a `parse error' message I don't understand.</a><br/>
68 <h1>Configuration questions:</h1>
70 <a href="#C1">C1. Why do I need a .fetchmailrc when running as root
71 on my own machine?</a><br/>
72 <a href="#C2">C2. How can I arrange for a fetchmail daemon to get
73 killed when I log out?</a><br/>
74 <a href="#C3">C3. How do I know what interface and address to use
75 with --interface?</a><br/>
76 <a href="#C4">C4. How can I set up support for sendmail's anti-spam
78 <a href="#C5">C5. How can I poll some of my mailboxes more/less
79 often than others?</a><br/>
80 <a href="#C6">C6. Fetchmail works OK started up manually, but not
81 from an init script.</a><br/>
82 <a href="#C7">C7. How can I forward mail to another
86 <h1>How to make fetchmail play nice with various MTAs:</h1>
88 <a href="#T1">T1. How can I use fetchmail with sendmail?</a><br/>
89 <a href="#T2">T2. How can I use fetchmail with qmail?</a><br/>
90 <a href="#T3">T3. How can I use fetchmail with exim?</a><br/>
91 <a href="#T4">T4. How can I use fetchmail with smail?</a><br/>
92 <a href="#T5">T5. How can I use fetchmail with SCO's MMDF?</a><br/>
93 <a href="#T6">T6. How can I use fetchmail with Lotus Notes?</a><br/>
94 <a href="#T7">T7. How can I use fetchmail with Courier IMAP?</a><br/>
95 <a href="#T8">T8. How can I use fetchmail with vbmailshield?</a><br/>
97 <h1>How to make fetchmail work with various servers:</h1>
99 <a href="#S1">S1. How can I use fetchmail with qpopper?</a><br/>
100 <a href="#S2">S2. How can I use fetchmail with Microsoft Exchange?</a><br/>
101 <a href="#S3">S3. How can I use fetchmail with HP OpenMail?</a><br/>
102 <a href="#S4">S4. How can I use fetchmail with Novell GroupWise?</a><br/>
103 <a href="#S5">S5. How can I use fetchmail with InterChange?</a><br/>
104 <a href="#S6">S6. How can I use fetchmail with MailMax?</a><br/>
105 <a href="#S7">S7. How can I use fetchmail with FTGate?</a><br/>
107 <h1>How to fetchmail work with specific ISPs:</h1>
109 <a href="#I1">I1. How can I use fetchmail with Compuserve RPA?</a><br/>
110 <a href="#I2">I2. How can I use fetchmail with Demon Internet's SDPS?</a><br/>
111 <a href="#I3">I3. How can I use fetchmail with usa.net's servers?</a><br/>
112 <a href="#I4">I4. How can I use fetchmail with geocities POP3 servers?</a><br/>
113 <a href="#I5">I5. How can I use fetchmail with Hotmail?</a><br/>
114 <a href="#I6">I6. How can I use fetchmail with MSN?</a><br/>
115 <a href="#I7">I7. How can I use fetchmail with SpryNet?</a><br/>
116 <a href="#I8">I8. How can I use fetchmail with comcast.net?</a><br/>
118 <h1>How to set up well-known security and authentication
121 <a href="#K1">K1. How can I use fetchmail with SOCKS?</a><br/>
122 <a href="#K2">K2. How can I use fetchmail with IPv6 and IPsec?</a><br/>
123 <a href="#K3">K3. How can I get fetchmail to work with ssh?</a><br/>
124 <a href="#K4">K4. What do I have to do to use the IMAP-GSS protocol?</a><br/>
125 <a href="#K5">K5. How can I use fetchmail with SSL?</a><br/>
127 <h1>Runtime fatal errors:</h1>
129 <a href="#R1">R1. Fetchmail isn't working, and -v shows `SMTP
130 connect failed' messages.</a><br/>
131 <a href="#R2">R2. When I try to configure an MDA, fetchmail doesn't
133 <a href="#R3">R3. Fetchmail dumps core when given an invalid rc
135 <a href="#R4">R4. Fetchmail dumps core in -V mode, but operates
136 normally otherwise.</a><br/>
137 <a href="#R5">R5. Running fetchmail in daemon mode doesn't
139 <a href="#R6">R6. Fetchmail randomly dies with socket errors.</a><br/>
140 <a href="#R7">R7. Fetchmail running as root stopped working after
141 an OS upgrade</a><br/>
142 <a href="#R8">R8. Fetchmail is timing out after fetching certain
143 messages but before deleting them</a><br/>
144 <a href="#R9">R9. Fetchmail is timing out during message fetches</a><br/>
145 <a href="#R10">R10. Fetchmail is dying with SIGPIPE.</a><br/>
146 <a href="#R11">R11. My server is hanging or emitting errors on CAPA.</a><br/>
147 <h1>Hangs and lockups:</h1>
149 <a href="#H1">H1. Fetchmail hangs when used with pppd.</a><br/>
150 <a href="#H2">H2. Fetchmail hangs during the MAIL FROM
152 <a href="#H3">H3. Fetchmail hangs while fetching mail.</a><br/>
155 <h1>Disappearing mail:</h1>
157 <a href="#D1">D1. I think I've set up fetchmail correctly, but I'm
158 not getting any mail.</a><br/>
159 <a href="#D2">D2. All my mail seems to disappear after a dropped
161 <a href="#D3">D3. Mail that was being fetched when I interrupted my
162 fetchmail seems to have been vanished.</a><br/>
165 <h1>Multidrop-mode problems:</h1>
167 <a href="#M1">M1. I've declared local names, but all my multidrop
168 mail is going to root anyway.</a><br/>
169 <a href="#M2">M2. I can't seem to get fetchmail to route to a local
170 domain properly.</a><br/>
171 <a href="#M3">M3. I tried to run a mailing list using multidrop,
172 and I have a mail loop!</a><br/>
173 <a href="#M4">M4. My multidrop fetchmail seems to be having DNS
175 <a href="#M5">M5. I'm seeing long DNS delays before each message is
177 <a href="#M6">M6. How do I get multidrop mode to work with
179 <a href="#M7">M7. Multidrop mode isn't parsing envelope addresses
180 from my Received headers as it should.</a><br/>
181 <a href="#M8">M8. Users are getting multiple copies of
185 <h1>Mangled mail:</h1>
187 <a href="#X1">X1. Spurious blank lines are appearing in the headers
188 of fetched mail.</a><br/>
189 <a href="#X2">X2. My mail client can't see a Subject
191 <a href="#X3">X3. Messages containing "From" at start of line are
192 being split.</a><br/>
193 <a href="#X4">X4. My mail is being mangled in a new and different
195 <a href="#X5">X5. Using POP3, retrievals seems to be fetching too
197 <a href="#X6">X6. My mail attachments are being dropped or
199 <a href="#X7">X7. Some mail attachments are hanging
201 <a href="#X8">X8. A spurious ) is being appended to my
204 <h1>Other problems:</h1>
206 <a href="#O1">O1. The --logfile option doesn't work if the logfile
207 doesn't exist.</a><br/>
208 <a href="#O2">O2. Every time I get a POP or IMAP message the header
209 is dumped to all my terminal sessions.</a><br/>
210 <a href="#O3">O3. Does fetchmail reread its rc file every poll
212 <a href="#O4">O4. Why do deleted messages show up again when I take
213 a line hit while downloading?</a><br/>
214 <a href="#O5">O5. Why is fetched mail being logged with my name,
215 not the real From address?</a><br/>
216 <a href="#O6">O6. I'm seeing long sendmail delays or hangs near the
217 start of each poll cycle.</a><br/>
218 <a href="#O7">O7. Why doesn't fetchmail deliver mail in date-sorted
220 <a href="#O8">O8. I'm using pppd. Why isn't my monitor option
222 <a href="#O9">O9. Why does fetchmail keep retrieving the same
223 messages over and over?</a><br/>
224 <a href="#O10">O10. Why is the received date on all my messages the
226 <a href="#O11">O11. I keep getting messages that say "Repoll
227 immediately" in my logs.</a><br/>
228 <a href="#O12">O12. Fetchmail no longer expunges mail on a 451 SMTP response.</a><br/>
229 <a href="#O13">O13. I want timestamp information in my fetchmail logs.</a>
234 <h2><a id="G1" name="G1">G1. What is fetchmail and why should I
237 <p>Fetchmail is a one-stop solution to the remote mail retrieval
238 problem for Unix machines, quite useful to anyone with an
239 intermittent PPP or SLIP connection to a remote mailserver. It can
240 collect mail using any variant of POP or IMAP and forwards via port
241 25 to the local SMTP listener, enabling all the normal
242 forwarding/filtering/aliasing mechanisms that would apply to local
243 mail or mail arriving via a full-time TCP/IP connection.</p>
245 <p>Fetchmail is not a toy or a coder's learning exercise, but an
246 industrial-strength tool capable of transparently handling every
247 retrieval demand from those of a simple single-user ISP connection
248 up to mail retrieval and rerouting for an entire client domain.
249 Fetchmail is easy to configure, unobtrusive in operation, powerful,
250 feature-rich, and well documented.</p>
252 <p>Fetchmail is <a href="http://www.opensource.org">open-source</a>
253 software. The openness of the sources is the strongest assurance of
254 quality you can have. Extensive peer review by a large,
255 multi-platform user community has shown that fetchmail is as near
256 bulletproof as the underlying protocols permit.</p>
258 <p>Fetchmail is licensed under the <a
259 href="http://gnu.org//copyleft/gpl.html">GNU General Public
262 <p>If you found this FAQ in the distribution, see the README for
263 fetchmail's full feature list.</p>
266 <h2><a id="G2" name="G2">G2. Where do I find the latest FAQ and
267 fetchmail sources?</a></h2>
269 <p>The latest HTML FAQ is available alongside the latest fetchmail
270 sources at the fetchmail home page: <a
271 href="http://www.catb.org/~esr/fetchmail">http://www.catb.org/~esr/fetchmail</a>.
272 You can also usually find both in the <a
273 href="http://sunsite.unc.edu/pub/Linux/system/mail/pop/!INDEX.html">
274 POP mail tools directory on Sunsite</a>.</p>
276 <p>A text dump of this FAQ is included in the fetchmail
277 distribution. Because it freezes at distribution release time, it
278 may not be completely current.</p>
281 <h2><a id="G3" name="G3">G3. I think I've found a bug. Will you fix
284 <p>Yes I will, provided you include enough diagnostic information
285 for me to go on. Send bugs to <a
286 href="mailto:fetchmail-friends@ccil.org">fetchmail-friends</a>.
287 When reporting bugs, please include the following:</p>
290 <li>Your operating system.</li>
292 <li>Your compiler version, if you built from source; otherwise, the
293 name and origin of the RPM or other binary package you
296 <li>A copy of your POP or IMAP server's greeting line.</li>
298 <li>The name and version of the SMTP listener or MDA you are
301 <li>Any command-line options you used.</li>
303 <li>The output of fetchmail -V called with whatever other
304 command-line options you used.</li>
307 <p>If you have FTP access to your remote mail account, and you have
308 any suspicion that the bug was triggered by a particular message,
309 please include a copy of the message that triggered the bug.</p>
311 <p>Often, the first thing I will do when you report a bug is tell
312 you to upgrade to the newest version of fetchmail, and then see if
313 the problem reproduces. So you'll probably save us both time if you
314 upgrade and test with the latest version <em>before</em> sending in
317 <p>If your bug is something that used to work but stopped working
318 when you upgraded, then you can help pin the bug down by trying <a
319 href="ftp://ftp.ccil.org/pub/esr/fetchmail/">intermediate versions
320 of fetchmail</a> until you identify the revision that broke your
321 feature. The smart way to do this is by binary search on the
322 version sequence. First, try the version halfway between your last
323 good one and the current one. If it works, the failure was
324 introduced in the upper half of the sequence; if it doesn't, the
325 failure was introduced in the lower half. Now bisect that half in
326 the same way. In a very few tries, you should be able to identify
327 the exact adjacent pair of versions between which your bug was
328 introduced -- and with information like that, I can usually come up
329 with a fix very quickly.</p>
331 <p>Another useful thing you can do, if you're using POP3, is to
332 test for IMAP4 support on your mailserver using the autoprobe
333 function of fetchmailconf. If you have IMAP4, and fetchmailconf
334 doesn't tell you it's broken, switch immediately. POP3 is a weak,
335 poorly-designed protocol with chronic problems, and the later
336 versions after RFC1725 actually get worse rather than better.
337 Changing over to IMAP4 may well make your problem go away -- and if
338 your ISP doesn't have IMAP4 support, bug them to supply it.</p>
340 <p>It is helpful if you include your .fetchmailrc file, but not
341 necessary unless your symptom seems to involve an error in
342 configuration parsing. If you do send in your .fetchmailrc, mask
343 the passwords first!</p>
345 <p>If fetchmail seems to run and fetch mail, but the headers look
346 mangled (that is, headers are missing or blank lines are inserted
347 in the headers) then read the FAQ items in section <a
348 href="#X1">X</a> before submitting a bug report. Pay special
349 attention to the item on <a href="#generic_mangling">diagnosing
350 mail mangling</a>. There are lots of ways for other programs in the
351 mail chain to screw up that look like fetchmail's fault, but you
352 may be able to fix these by tweaking your configuration.</p>
354 <p>A transcript of the failed session with -v -v (yes, that's
355 <em>two</em> -v options, enabling debug mode) will almost always be
356 useful. It is very important that the transcript include your
357 POP/IMAP server's greeting line, so I can identify it in case of
358 server problems. This transcript will not reveal your passwords,
359 which are specially masked out precisely so transcripts can be
362 <p>If you upgraded your fetchmail and something broke, you should
363 include session transcripts with -v -v of both the working and
364 failing versions. Very often, the source of the problem can
365 instantly identified by looking at the differences in protocol
368 <p>If the bug involves a core dump or hang, a gdb stack trace is
369 good to have. (Bear in mind that you can attach gdb to a running
370 but hung process by giving the process ID as a second argument.)
371 You will need to reconfigure with:</p>
374 CFLAGS=-g LDFLAGS=" " ./configure
377 <p>Then rebuild in order to generate a version that can be
380 <p>Best of all is a mail file which, when fetched, will reproduce
381 the bug under the latest (current) version.</p>
383 <p>Any bug I can reproduce will usually get fixed very quickly,
384 often within 48 hours. Bugs I can't reproduce are a crapshoot. If
385 the solution isn't obvious when I first look, it may evade me for a
386 long time (or to put it another way, fetchmail is well enough
387 tested that the easy bugs have long since been found). So if you
388 want your bug fixed rapidly, it is not just sufficient but nearly
389 <em>necessary</em> that you give me a way to reproduce it.</p>
392 <h2><a id="G4" name="G4">G4. I have this idea for a neat feature.
393 Will you add it?</a></h2>
395 <p>Probably not. Most of the feature suggestions I get are for ways
396 to set various kinds of administrative policy or add more spam
397 filtering (the most common one, which I used to get about four
398 million times a week and got <em>really</em> tired of, is for
399 tin-like kill files).</p>
401 <p>You can do spam filtering better with procmail or maildrop on
402 the server side and (if you're the server sysadmin) sendmail.cf
403 domain exclusions. You can do other policy things better with the
404 <code>mda</code> option and script wrappers around fetchmail. If
405 it's a prime-time-vs.-non-prime-time issue, ask yourself whether a
406 wrapper script called from crontab would do the job.</p>
408 <p>I'm not going to do these; fetchmail's job is transport, not
409 policy, and I refuse to change it from doing one thing well to
410 attempting many things badly. One of my objectives is to keep
411 fetchmail simple so it stays reliable.</p>
413 <p>For reasons fetchmail doesn't have other commonly-requested
414 features (such as password encryption, or multiple concurrent polls
415 from the same instance of fetchmail) see the <a
416 href="http://www.catb.org/~esr/fetchmail/design-notes.html">design
419 <p>Fetchmail is a mature project, no longer in constant active
420 development. It is no longer my top project, and I am going to be
421 quite reluctant to add features that might either jeopardize its
422 stability or involve me in large amounts of coding.</p>
424 <p>All that said, if you have a feature idea that really is about a
425 transport problem that can't be handled anywhere but fetchmail, lay
426 it on me. I'm very accommodating about good ideas.</p>
429 <h2><a id="G5" name="G5">G5. I want to make fetchmail behave like
430 Outlook Express.</a></h2>
432 <p>The second-most-requested feature for fetchmail, after
433 content-based filtering, is the ability to have it remove messages
434 from a maildrop after N days, typically to be used with the
435 <code>keep</code> option as a sort of poor man's newsgroup
436 facility. Microsoft's Outlook Express supports this.</p>
438 <p>This feature won't be added either. Repeat after me: fetchmail's
439 job is transport, not policy. If you want this, write a Perl or
440 Python script, to be run from a cron job, that deletes old messages
441 off your maildrop. Send it to me and I'll put it in the contrib
445 <h2><a id="G6" name="G6">G6. Is there a mailing list for exchanging
448 <p>There is a fetchmail-friends list
449 (fetchmail-friends@lists.ccil.org) for people who want to discuss
450 fixes and improvements in fetchmail and help co-develop it. It's a
451 MailMan list, which you can sign up for at <a
452 href="http://lists.ccil.org/mailman/listinfo/fetchmail-friends">http://lists.ccil.org/mailman/listinfo/fetchmail-friends</a>.
453 There is also an announcements-only list,
454 fetchmail-announce@lists.ccil.org, which you can sign up for at <a
455 href="http://lists.ccil.org/mailman/listinfo/fetchmail-announce">http://lists.ccil.org/mailman/listinfo/fetchmail-announce</a>.</p>
458 <h2><a id="G7" name="G7">G7. So, what's this I hear about a
459 fetchmail paper?</a></h2>
461 <p>The fetchmail development was also a sociological experiment, an
462 extended test to see if my theory about the critical features of
463 the Linux development model is correct.</p>
465 <p>The experiment was a success. I wrote a paper about it titled <a
466 href="http://www.catb.org/~esr/writings/cathedral.html">The
467 Cathedral and the Bazaar</a> which was first presented at Linux
468 Kongress '97 in Bavaria and very well received there. It was also
469 given at Atlanta Linux Expo, Linux Pro '97 in Warsaw, and the first
470 Perl Conference, at UniForum '98, and was the basis of an invited
471 presentation at Usenix '98. The folks at Netscape tell me it helped
473 href="http://www.netscape.com/newsref/pr/newsrelease558.html">give
474 away the source for Netscape Communicator</a>.</p>
476 <p>If you're reading a non-HTML dump of this FAQ, you can find the
477 paper on the Web with a search for that title.</p>
480 <h2><a id="G8" name="G8">G8. What is the best server to use with
483 <p>The short answer: IMAP 2000 running over Unix.</p>
485 <p>Here's a longer answer:</p>
487 <p>Fetchmail will work with any POP, IMAP, ETRN, or ODMR server
488 that conforms to the relevant RFCs (and even some outright broken
489 ones like <a href="#S2">Microsoft Exchange</a> and <a
490 href="#S6">Novell GroupWise</a>). This doesn't mean it works
491 equally well with all, however. POP2 servers, and POP3 servers
492 without LAST, limit fetchmail's capabilities in various ways
493 described on the manual page.</p>
495 <p>Most modern Unixes (and effectively all Linux/*BSD systems) come
496 with POP3 support preconfigured (but beware of the horribly broken
497 POP3 server mentioned in <a href="#D2">D2</a>). An increasing
498 minority also feature IMAP (you can detect IMAP support by running
499 fetchmail in AUTO mode, or by using the `Probe for supported
500 protocols' function in the fetchmailconf utility).</p>
502 <p>If you have the option, we recommend using or installing an
503 IMAP4rev1 server; it has the best facilities for tracking message
504 `seen' states. It also recovers from interrupted connections more
505 gracefully than POP3, and enables some significant performance
506 optimizations. The new <a
507 href="ftp://ftp.cac.washington.edu/imap/imap.tar.Z">IMAP 2000</a>
508 is particularly nice, as it supports CRAM-MD5 so you don't have to
509 ship your mail password over the net en clair (fetchmail
510 autodetects this capability). Older versions had support for GSSAPI
511 giving a similar effect.</p>
513 <p>Don't be fooled by NT/Exchange propaganda. M$ Exchange is just
514 plain broken (see item <a href="#S2">S2</a>) and NT cannot handle
515 the sustained load of a high-volume remote mail server. Even
516 Microsoft itself knows better than to try this; their own Hotmail
517 service runs over Solaris! For extended discussion, see John
518 Kirch's excellent <a href="http://unix-vs-nt.org/kirch/">white
519 paper</a> on Unix vs. NT performance.</p>
521 <p>Source for a high-quality supported implementation of POP is
522 available from the <a
523 href="ftp://ftp.qualcomm.com/eudora/servers/unix/popper/">Eudora
524 FTP site</a>. Don't use 2.5, which has a rather restrictive
525 license. The 2.5.2 version appears to restore the open-source
526 license of previous versions.</p>
529 <h2><a id="G9" name="G9">G9. What is the best mail program to use
530 with fetchmail?</a></h2>
532 <p>Fetchmail will work with all popular <a href="#T1">mail
533 transport programs</a>. It also doesn't care which user agent you
534 use, and user agents are as a rule almost equally indifferent to
535 how mail is delivered into your system mailbox. So any of the
536 popular Unix mail agents -- <a
537 href="http://www.myxa.com/old/elm.html">elm</a>, <a
538 href="http://www.washington.edu/pine/">pine</a>, <a
539 href="http://www.cs.indiana.edu/docproject/mail/mh.html">mh</a>, or
540 <a href="http://www.mutt.org">mutt</a> -- will work fine with
543 <p>All this having been said, I can't resist putting in a discreet
544 plug for <a href="http://www.mutt.org">mutt</a>. My own personal
545 mail setup is sendmail plus fetchmail plus mutt. Mutt's interface
546 is only a little different from that of its now-moribund ancestor
547 elm, but its excellent handling of MIME and PGP put it in a class
548 by itself. You won't need its built-in POP3 support, though; most
549 of the mutt developers will cheerfully admit that fetchmail's is
553 <h2><a id="G10" name="G10">G10. How can I avoid sending my password
556 <p>Depending on what your mail server you are talking to, this
557 ranges from trivial to impossible. It may even be next to
560 <p>Most people use fetchmail over phone wires (whether plain old
561 copper or DSL), which are hard to tap. Anybody with the skill and
562 resources to do this could get into your server mailbox with much less
563 effort by subverting the server host. So if your provider setup is
564 phone-company wire going straight into a service box, you probably
565 don't need to worry.</p>
567 <p>In general there is little point in trying to secure your fetchmail
568 transaction unless you trust the security of the server host you are
569 retrieving mail from. Your vulnerability is more likely to be an
570 insecure local network on the server end (e.g. to somebody with a
571 TCP/IP packet sniffer intercepting Ethernet traffic between the modem
572 concentrator or DSL POP you dial in to and the mailserver host).</p>
574 <p>Having realized this, you need to ask whether password
575 encryption alone will really address your security exposure. If you
576 think you might be snooped between server and client, it's better
577 to use end-to-end encryption on your whole mail stream so none of
578 it can be read. One of the advantages of fetchmail over
579 conventional SMTP-push delivery is that you may be able to arrange
580 this by using ssh(1); see <a href="#K3">K3</a>.</p>
582 <p>Note that ssh is not a complete privacy solution either, as your
583 mail could have been snooped in transit to your POP server from
584 wherever it originated. For best security, agree with your
585 correspondents to use a tool such as <a
586 href="http://www.gnupg.org/">GPG</a> (Gnu Privacy Guard) or PGP
587 (Pretty Good Privacy).</p>
589 <p>If ssh/sshd isn't available, or you find it too complicated for
590 you to set up, password encryption will at least keep a malicious
591 cracker from deleting your mail, and require him to either tap your
592 connection continuously or crack root on the server in order to
595 <p>You can deduce what encryptions your mail server has available
596 by looking at the server greeting line (and, for IMAP, the response
597 to a CAPABILITY query). Do a <code>fetchmail -v</code> to see
598 these, or telnet direct to the server port (110 for POP3, 143 for
601 <p>If your mailserver is using IMAP 2000, you'll have CRAM-MD5
602 support built in. Fetchmail autodetects this; you can skip the rest
605 <p>The POP3 facility you are most likely to have available is APOP.
606 This is a POP3 feature supported by many servers (fetchmailconf's
607 autoprobe facility will detect it and tell you if you have it). If
608 you see something in the greeting line that looks like an
609 angle-bracket-enclosed Internet address with a numeric left-hand
610 part, that's an APOP challenge (it will vary each time you log in).
611 You can register a secret on the host (using
612 <code>popauth(8)</code> or some program like it). Specify the
613 secret as your password in your .fetchmailrc; it will be used to
614 encrypt the current challenge, and the encrypted form will be sent
615 back the the server for verification.</p>
617 <p>Alternatively, you may have Kerberos available. This may require
618 you to set up some magic files in your home directory on your
619 client machine, but means you can omit specifying any password at
622 <p>Fetchmail supports two different Kerberos schemes. One is a POP3
623 variant called KPOP; consult the documentation of your mail server
624 to see if you have it (one clue is the string "krb-IV" in the
625 greeting line on port 110). The other is an IMAP and POP3 facility
626 described by RFC1731 and RFC1734. You can tell if this one is
627 present by looking for AUTH=KERBEROS_V4 in the CAPABILITY
630 <p>If you are fetching mail from a CompuServe POP3 account, you can
631 use their RPA authentication (which works much like APOP). See <a
632 href="#I1">I1</a> for details. If you are fetching mail from
633 Microsoft Exchange using IMAP, you will be able to use NTLM.</p>
635 <p>Your POP3 server may have the RFC1938 OTP capability to use
636 one-time passwords (if it doesn't, you can get OTP patches for the
637 2.2 version of the Qualcomm popper from <a href="#cmetz">Craig
638 Metz</a>). To check this, look for the string "otp-" in the
639 greeting line. If you see it, and your fetchmail was built with
640 OPIE support compiled in (see the distribution INSTALL file),
641 fetchmail will detect it also. When using OTP, you will specify a
642 password but it will not be sent en clair.</p>
644 <p>You can get both POP3 and IMAP OTP patches from <a id="cmetz"
645 name="cmetz">Craig Metz</a> at <a
646 href="http://www.inner.net/pub/">http://www.inner.net/pub/</a>.</p>
648 <p>These patches use a SASL authentication method named "X-OTP"
649 because there is not currently a standard way to do this; fetchmail
650 also uses this method, so the two will interoperate happily. They
651 better, because this is how Craig gets his mail ;-)</p>
653 <p>Finally, you can use <a href="#K5">SSL</a> for complete
654 end-to-end encryption if you have an SSL-enabled mailserver.</p>
657 <h2><a id="G11" name="G11">G11. Is any special configuration needed
658 to use a dynamic IP address?</a></h2>
660 <p>Yes. In order to avoid giving indigestion to certain picky MTAs
661 (notably <a href="#T3">exim</a>), fetchmail always makes the RCPT
662 TO address it feeds the MTA a fully qualified one with a hostname
663 part. Normally it does this by appending @ and "localhost", but
664 when you are using Kerberos or ETRN mode it will append @ and your
665 machine's fully-qualified domain name (FQDN).</p>
667 <p>Appending the FQDN can create problems when fetchmail is running
668 in daemon mode and outlasts the dynamic IP address assignment your
669 client machine had when it started up.</p>
671 <p>Since the new IP address (looked up at RCPT TO interpretation
672 time) doesn't match the original, the most benign possible result
673 is that your MTA thinks it's seeing a relaying attempt and refuses.
674 More frequently, fetchmail will try to connect to a nonexistent
675 host address and time out. Worst case, you could up forwarding your
676 mail to the wrong machine!</p>
678 <p>Use the <code>smtpaddress</code> option to force the appended
679 hostname to one with a (fixed) IP address of 127.0.0.1 in your
680 <code>/etc/hosts</code>. (The name `localhost' will usually work;
681 or you can use the IP address itself).</p>
683 <p>Only one fetchmail option interacts directly with your IP
684 address, `<code>interface</code>'. This option can be used to set
685 the gateway device and restrict the IP address range fetchmail will
686 use. Such a restriction is sometimes useful for security reasons,
687 especially on multihomed sites. See <a href="#C3">C3</a>.</p>
689 <p>I recommend against trying to set up the <code>interface</code>
690 option when initially developing your poll configuration -- it's
691 never necessary to do this just to get a link working. Get the link
692 working first, observe the actual address range you see on
693 connections, and add an <code>interface</code> option (if you need
696 <p>You can't use ETRN if you have a dynamic IP address (your ISP
697 changes your IP address occasionally, possibly with every connect).
698 You need to have your own registered domain and a definite IP
699 address registered for that domain. The server needs to be
700 configured to accept mail for your domain but then queue it to
701 forward to your machine. ETRN just tells to server to flush its
702 queue for your domain. Fetchmail doesn't actually get the mail in
705 <p>You can use On-Demand Mail Relay (ODMR) with a dynamic IP
706 address; that's what it was designed for, and it provides
707 capabilities very similar to ETRN. Unfortunately ODMR servers are
708 not yet widely deployed, as of early 2001.</p>
710 <p>If you're using a dynamic-IP configuration, one other
711 (non-fetchmail) problem you may run into with outgoing mail is that
712 some sites will bounce your email because the hostname your giving
713 them isn't real (and doesn't match what they get doing a reverse
714 DNS on your dynamically-assigned IP address). If this happens, you
715 need to hack your sendmail so it masquerades as your host.
722 <p>in your <code>sendmail.cf</code> will work, or you can set</p>
725 MASQUERADE_AS(smarthost.here)
728 <p>in the m4 configuration and do a reconfigure. (In both cases,
729 replace <code>smarthost.here</code> with the actual name of your
730 mailhost.) See the <a
731 href="http://www.lege.com/sendmail-FAQ.txt">sendmail FAQ</a> for
735 <h2><a id="G12" name="G12">G12. Is any special configuration needed
736 to use firewalls?</a></h2>
738 <p>No. You can use fetchmail with SOCKS, the standard tool for
739 indirecting TCP/IP through a firewall. You can find out about
740 SOCKS, and download the SOCKS software including server and client
741 code, at the <a href="http://www.socks.nec.com/">SOCKS distribution
744 <p>The specific recipe for using fetchmail with a firewall is at <a
745 href="#K1">K1</a></p>
748 <h2><a id="G13" name="G13">G13. Is any special configuration needed
749 to <em>send</em> mail?</a></h2>
751 <p>A user asks: but how do we send mail out to the POP3 server? Do
752 I need to implement another tool or will fetchmail do this too?</p>
754 <p>Fetchmail only handles the receiving side. The sendmail or other
755 preinstalled MTA on your client machine will handle sending mail
756 automatically; it will ship mail that is submitted while the
757 connection is active, and put mail that is submitted while the
758 connection is inactive into the outgoing queue.</p>
760 <p>Normally, sendmail is also run periodically (every 15 minutes on
761 most Linux systems) in a mode that tries to ship all the mail in
762 the outgoing queue. If you have set up something like pppd to
763 automatically dial out when your kernel is called to open a TCP/IP
764 connection, this will ensure that the mail gets out.</p>
767 <h2><a id="G14" name="G14">G14. Is fetchmail
768 Y2K-compliant?</a></h2>
770 <p>Fetchmail is fully Y2K-compliant.</p>
772 <p>Fetchmail could theoretically have problems when the 32-bit
773 time_t counters roll over in 2038, but I doubt it. Timestamps
774 aren't used for anything but log entry generation. Anyway, if you
775 aren't running on a 64-bit machine by then, you'll deserve to
779 <h2><a id="G15" name="G15">G15. Is there a way in fetchmail to
780 support disconnected IMAP mode?</a></h2>
782 <p>No. Fetchmail is a mail transport agent, best understood as a
783 protocol gateway between POP3/IMAP servers and SMTP. Disconnected
784 operation requires an elaborate interactive client. It's a very
785 different problem.</p>
788 <h2><a id="G16" name="G16">G16. How will fetchmail perform under
789 heavy loads?</a></h2>
791 <p>Fetchmail streams message bodies line-by-line; the most core it
792 ever requires per message is enough memory to hold the RFC822
793 header, and that storage is freed when body processing begins. It
794 is, accordingly, quite economical in its use of memory.</p>
796 <p>After startup time, a fetchmail running in daemon mode stats its
797 configuration file once per poll cycle to see whether it has
798 changed and should be rescanned. Other than that, a fetchmail in
799 normal operation doesn't touch the disk at all; that job is left up
800 to the MTA or MDA the fetchmail talks to.</p>
802 <p>Fetchmail's performance is usually bottlenecked by latency on
803 the POP server or (less often) on the TCP/IP link to the server.
804 This is not a problem readily solved by tuning fetchmail, or even
805 by buying more TCP/IP capacity (which tends to improve bandwidth
806 but not necessarily latency).</p>
809 <h2><a id="B1" name="B1">B1. Make coughs and dies when building on
812 <p>The vendor-supplied make on FreeBSD systems can only be used
813 within FreeBSD's "scope", e.g. the ports collection. Type "gmake"
814 to run GNU make and better things will happen.</p>
817 <h2><a id="B2" name="B2">B2. Lex bombs out while building the
818 fetchmail lexer.</a></h2>
820 <p>In the immortal words of Alan Cox the last time this came up:
821 ``Take the Solaris lex and stick it up the backside of a passing
822 Sun salesman, then install <a
823 href="ftp://ftp.gnu.org/pub/non-gnu/flex/">flex</a> and use that.
824 All will be happier.''</p>
826 <p>I couldn't have put it better myself, and ain't going to try
829 <p>(The same problem has been reported under HP-UX v10.20 and
833 <h2><a id="B3" name="B3">B3. I get link failures when I try to
834 build fetchmail.</a></h2>
836 <p>If you get errors resembling these</p>
839 mxget.o(.text+0x35): undefined referenceto `__res_search'
840 mxget.o(.text+0x99): undefined reference to`__dn_skipname'
841 mxget.o(.text+0x11c): undefined reference to`__dn_expand'
842 mxget.o(.text+0x187): undefined reference to`__dn_expand'
843 make: *** [fetchmail] Error 1
846 <p>then you must add "-lresolv" to the LOADLIBS line in your
847 Makefile once you have installed the `bind' package.</p>
849 <p>If you get link errors involving <tt>dcgettext</tt>, like
853 rcfile_y.o: In function `yyparse':
854 rcfile_y.o(.text+0x3aa): undefined reference to `dcgettext__'
855 rcfile_y.o(.text+0x4f2): undefined reference to `dcgettext__'
856 rcfile_y.o(.text+0x5ee): undefined reference to `dcgettext__'
857 rcfile_y.o: In function `yyerror':
858 rcfile_y.o(.text+0xc7c): undefined reference to `dcgettext__'
859 rcfile_y.o(.text+0xcc8): undefined reference to `dcgettext__'
860 rcfile_y.o(.text+0xdf9): more undefined references to `dcgettext__' follow
863 <p>reconfigure with <tt>configure --with-included-gettext</tt>.
864 This is due to some brain-damage in the GNU internationalization
868 <h2><a id="B4" name="B4">B4. I get build failures in the intl
871 <p>Reconfigure with <tt>--disable-nls</tt> and recompile.</p>
873 <p>GNU gettext is an overengineered, fragile pile of crap. I have
874 teetered on the brink of removing support for it entirely several
878 <h2><a id="F1" name="F1">F1. Why does my old .fetchmailrc file no
879 longer work?</a></h2>
881 <h3>If your file predates 5.8.9</h3>
883 <p>If you were using ETRN mode, change your <tt>smtphost</tt>
884 option to a <tt>fetchdomains</tt> option.</p>
886 <h3>If your file predates 5.8.3</h3>
888 <p>The `via localhost' special case for use with ssh tunnelling is
889 gone. Use the %h feature of <tt>plugin</tt> instead.</p>
891 <h3>If your file predates 5.6.8</h3>
893 <p>In 5.6.8, the <tt>preauth</tt> keyword and option were changed
894 back to <tt>auth</tt>. The <tt>preauth</tt> synonym will still be
895 supported through a few more point releases.</p>
897 <h3>If your file predates 5.6.5</h3>
899 <p>The <tt>imap-gss</tt>, <tt>imap-k4</tt>, and <tt>imap-login</tt>
900 protocol types are gone. This is a result of a major re-factoring
901 of the authentication machinery; fetchmail can now use Kerberos V4
902 and GSSAPI not just with IMAP but with POP3 servers that have
903 RFC1734 support for the AUTH command.</p>
905 <p>When trying to identify you to an IMAP or POP mailserver,
906 fetchmail now first tries methods that don't require a password
907 (GSSAPI, KERBEROS_IV); then it looks for methods that mask your
908 password (CRAM-MD5, X-OTP); and only if it the server doesn't
909 support any of those will it ship your password en clair.</p>
911 <p>Setting the <tt>preauth</tt> option to any value other than
912 `password' will prevent from looking for a password in your
913 <tt>.netrc</tt> file or querying for it at startup time.</p>
915 <h3>If your file predates 5.1.0</h3>
917 <p>In 5.1.0, the <tt>auth</tt> keyword and option were changed to
918 <tt>preauth</tt>.</p>
920 <h3>If your file predates 4.5.5</h3>
922 <p>If the <code>dns</code> option is on (the default), you may need
923 to make sure that any hostname you specify (for mail hosts or for
924 an SMTP target) is a canonical fully-qualified hostname). In order
925 to avoid DNS overhead and complications, fetchmail no longer tries
926 to derive the fetchmail client machine's canonical DNS name at
929 <h3>If your file predates 4.0.6:</h3>
931 <p>Just after the `<code>via</code>' option was introduced, I
932 realized that the interactions between the `<code>via</code>',
933 `<code>aka</code>', and `<code>localdomains</code>' options were
934 out of control. Their behavior had become complex and confusing, so
935 much so that I was no longer sure I understood it myself. Users
936 were being unpleasantly surprised.</p>
938 <p>Rather than add more options or crock the code, I re-thought it.
939 The redesign simplified the code and made the options more
940 orthogonal, but may have broken some complex multidrop
943 <p>Any multidrop configurations that depended on the name just
944 after the `<code>poll</code>' or `<code>skip</code>' keyword being
945 still interpreted as a DNS name for address-matching purposes, even
946 in the presence of a `<code>via</code>' option, will break.</p>
948 <p>It is theoretically possible that other unusual configurations
949 (such as those using a non-FQDN poll name to generate Kerberos IV
950 tickets) might also break; the old behavior was sufficiently murky
951 that we can't be sure. If you think this has happened to you,
952 contact the maintainer.</p>
954 <h3>If your file predates 3.9.5:</h3>
956 <p>The `<code>remote</code>' keyword has been changed to
957 `<code>folder</code>'. If you try to use the old keyword, the
958 parser will utter a warning.</p>
960 <h3>If your file predates 3.9:</h3>
962 <p>It could be because you're using a .fetchmailrc that's written
963 in the old popclient syntax without an explicit
964 `<code>username</code>' keyword leading the first user entry
965 attached to a server entry.</p>
967 <p>This error can be triggered by having a user option such as
968 `<code>keep</code>' or `<code>fetchall</code>' before the first
969 explicit username. For example, if you write</p>
972 poll openmail protocol pop3
973 keep user "Hal DeVore" there is hdevore here
976 <p>the `<code>keep</code>' option will generate an entire user
977 entry with the default username (the name of fetchmail's invoking
980 <p>The popclient compatibility syntax was removed in 4.0. It
981 complicated the configuration file grammar and confused users.</p>
983 <h3>If your file predates 2.8:</h3>
985 <p>The `<code>interface</code>', `<code>monitor</code>' and
986 `<code>batchlimit</code>' options changed after 2.8.</p>
988 <p>They used to be global options with `<code>set</code>' syntax
989 like the batchlimit and logfile options. Now they're per-server
990 options, like `<code>protocol</code>'.</p>
992 <p>If you had something like</p>
995 set interface = "sl0/10.0.2.15"
998 <p>in your .fetchmailrc file, simply delete that line and insert
999 `interface sl0/10.0.2.15' in the server options part of your
1000 `defaults' declaration.</p>
1002 <p>Do similarly for any `<code>monitor</code>' or
1003 `<code>batchlimit</code>' options.</p>
1006 <h2><a id="F2" name="F2">F2. The .fetchmailrc parser won't accept
1007 my all-numeric user name.</a></h2>
1009 <p>Either upgrade to a post-5.0.5 fetchmail or put string quotes
1012 <p>The configuration file parser in older fetchmail versions
1013 treated any all-numeric token as a number, which confused it when
1014 it was expecting a name. String quoting forces the token's
1017 <p>The lexical analyzer in 5.0.6 and beyond is smarter and assumes
1018 any token following "username" or "password" is a string.</p>
1021 <h2><a id="F3" name="F3">F3. The .fetchmailrc parser won't accept
1022 my host or username beginning with `no'.</a></h2>
1024 <p>See <a href="#F2">F2</a>. You're caught in an unfortunate crack
1025 between the newer-style syntax for negated options (`no keep', `no
1026 rewrite' etc.) and the older style run-on syntax (`nokeep',
1027 `norewrite' etc.).</p>
1029 <p>Upgrade to a 5.0.6 or later fetchmail, or put string quotes
1030 around your token.</p>
1033 <h2><a id="F4" name="F4">F4. I'm getting a `parse error' message I
1034 don't understand.</a></h2>
1036 <p>The most common cause of mysterious parse errors is putting a
1037 server option after a user option. Check the manual page; you'll
1038 probably find that by moving one or more options closer to the
1039 `poll' keyword you can eliminate the problem.</p>
1041 <p>Yes, I know these ordering restrictions are hard to understand.
1042 Unfortunately, they're necessary in order to allow the `defaults'
1043 feature to work.</p>
1046 <h2><a id="C1" name="C1">C1. Why do I need a .fetchmailrc when
1047 running as root on my own machine?</a></h2>
1049 <p>Ian T. Zimmerman <itz@rahul.net> asked:</p>
1051 <p>On the machine where I'm the only real user, I run fetchmail as
1052 root from a cron job, like this:</p>
1055 fetchmail -u "itz" -p POP3 -s bolero.rahul.net
1058 <p>This used to work as is (with no .fetchmailrc file in root's
1059 home directory) with the last version I had (1.7 or 1.8, I don't
1060 remember). But with 2.0, it RECPs all mail to the local root user,
1061 unless I create a .fetchmailrc in root's home directory
1065 skip bolero.rahul.net proto POP3
1069 <p>It won't work if the second line is just "<code>user
1070 itz</code>". This is silly.</p>
1072 <p>It seems fetchmail decides to RECP the `default local user'
1073 (i.e. the uid running fetchmail) unless there are local aliases,
1074 and the `default' aliases (itz->itz) don't count. They
1079 <p>No they shouldn't. I thought about this for a while, and I don't
1080 much like the conclusion I reached, but it's unavoidable. The
1081 problem is that fetchmail has no way to know, in general, that a
1082 local user `itz' actually exists.</p>
1084 <p>"Ah!" you say, "Why doesn't it check the password file to see if
1085 the remote name matches a local one?" Well, there are two
1088 <p>One: it's not always possible. Suppose you have an SMTP host
1089 declared that's not the machine fetchmail is running on? You
1092 <p>Two: How do you know server itz and SMTP-host itz are the same
1093 person? They might not be, and fetchmail shouldn't assume they are
1094 unless local-itz can explicitly produce credentials to prove it
1095 (that is, the server-itz password in local-itz's .fetchmailrc
1098 <p>Once you start running down possible failure modes and thinking
1099 about ways to tinker with the mapping rules, you'll quickly find
1100 that all the alternatives to the present default are worse or
1101 unacceptably more complicated or both.</p>
1104 <h2><a id="C2" name="C2">C2. How can I arrange for a fetchmail
1105 daemon to get killed when I log out?</a></h2>
1107 <p>The easiest way to dispatch fetchmail on logout (which will work
1108 reliably only if you have just one login going at any time) is to
1109 arrange for the command `fetchmail -q' to be called on logout.
1110 Under bash, you can arrange this by putting `fetchmail -q' in the
1111 file `~/.bash_logout'. Most csh variants execute `~/.logout' on
1112 logout. For other shells, consult your shell manual page.</p>
1114 <p>Automatic startup/shutdown of fetchmail is a little harder to
1115 arrange if you may have multiple login sessions going. In the
1116 contrib subdirectory of the fetchmail distribution there is some
1117 shell code you can add to your .bash_login and .bash_logout
1118 profiles that will accomplish this. Thank James Laferriere
1119 <babydr@nwrain.net> for it.</p>
1121 <p>Some people start up and shut down fetchmail using the ppp-up
1122 and ppp-down scripts of pppd.</p>
1125 <h2><a id="C3" name="C3">C3. How do I know what interface and
1126 address to use with --interface?</a></h2>
1128 <p>This depends a lot on your local networking configuration (and
1129 right now you can't use it at all except under Linux and the newer
1130 BSDs). However, here are some important rules of thumb that can
1131 help. If they don't work, ask your local sysop or your Internet
1134 <p>First, you may not need to use --interface at all. If your
1135 machine only ever does SLIP or PPP to one provider, it's almost
1136 certainly by a point to point modem connection to your provider's
1137 local subnet that's pretty secure against snooping (unless someone
1138 can tap your phone or the provider's local subnet!). Under these
1139 circumstances, specifying an interface address is fairly
1142 <p>What the option is really for is sites that use more than one
1143 provider. Under these circumstances, typically one of your provider
1144 IP addresses is your mailserver (reachable fairly securely via the
1145 modem and provider's subnet) but the others might ship your packets
1146 (including your password) over unknown portions of the general
1147 Internet that could be vulnerable to snooping. What you'll use
1148 --interface for is to make sure your password only goes over the
1149 one secure link.</p>
1151 <p>To determine the device:</p>
1154 <li>If you're using a SLIP link, the correct device is probably
1157 <li>If you're using a PPP link, the correct device is probably
1160 <li>If you're using a direct connection over a local network such
1161 as an ethernet, use the command `netstat -r' to look at your
1162 routing table. Try to match your mailserver name to a destination
1163 entry; if you don't see it in the first column, use the `default'
1164 entry. The device name will be in the rightmost column.</li>
1167 <p>To determine the address and netmask:</p>
1170 <li>If you're talking to slirp, the correct address is probably
1171 10.0.2.15, with no netmask specified. (It's possible to configure
1172 slirp to present other addresses, but that's the default.)</li>
1174 <li>If you have a static IP address, run `ifconfig <device>',
1175 where <device> is whichever one you've determined. Use the IP
1176 address given after "inet addr:". That is the IP address for your
1177 end of the link, and is what you need. You won't need to specify a
1180 <li>If you have a dynamic IP address, your connection IP will vary
1181 randomly over some given range (that is, some number of the least
1182 significant bits change from connection to connection). You need to
1183 declare an address with the variable bits zero and a complementary
1184 netmask that sets the range.</li>
1187 <p>To illustrate the rule for dynamic IP addresses, let's suppose
1188 you're hooked up via SLIP and your IP provider tells you that the
1189 dynamic address pool is 255 addresses ranging from 205.164.136.1 to
1190 205.164.136.255. Then</p>
1193 interface "sl0/205.164.136.0/255.255.255.0"
1196 <p>would work. To range over any value of the last two octets
1197 (65536 addresses) you would use</p>
1200 interface "sl0/205.164.0.0/255.255.0.0"
1204 <h2><a id="C4" name="C4">C4. How can I set up support for
1205 sendmail's anti-spam features?</a></h2>
1207 <p>This answer covers versions of sendmail from 8.9.3-20 (the
1208 version installed in Red Hat 6.2) upwards. If you have an older
1209 version, upgrade to sendmail 8.9.</p>
1211 <p>Stock sendmails can now do anti-spam exclusions based on a
1212 database of filter rules. The human-readable form of the database
1213 is at <tt>/etc/mail/access</tt>. The database itself is at
1214 <tt>/etc/mail/access.db</tt>.</p>
1216 <p>The table itself uses email addresses, domain names, and network
1217 numbers as keys. For example,</p>
1220 spammer@aol.com REJECT
1221 cyberspammer.com REJECT
1225 <p>would refuse mail from spammer@aol.com, any user from
1226 cyberspammer.com (or any host within the cyberspammer.com domain),
1227 and any host on the 192.168.212.* network. (This feature can be
1228 used to do other things as well; see the <a
1229 href="http://www.sendmail.org/m4/anti-spam.html">sendmail
1230 documentation</a> for details)</p>
1232 <p>To actually set up the database, run</p>
1235 makemap hash deny <deny
1238 <p>in /etc/mail.</p>
1240 <p>To test, send a message to your mailing address from that host
1241 and then pop off the message with fetchmail, using the -v argument.
1242 You can monitor the SMTP transaction, and when the FROM address is
1243 parsed, if sendmail sees that it is an address in spamlist,
1244 fetchmail will flush and delete it.</p>
1246 <p>Under no circumstances put your <strong>mailhost</strong> or
1247 <strong>any host you accept mail from</strong> using fetchmail into
1248 your reject file. You <strong>will</strong> lose mail if you do
1252 <h2><a id="C5" name="C5">C5. How can I poll some of my mailboxes
1253 more/less often than others?</a></h2>
1255 <p>Use the <cite>interval</cite> keyword on the ones that should be
1256 checked less often. For example, if you do a poll every 5 minutes,
1257 and want to poll some mailboxes every 5 minutes and some every 30
1258 minutes, use something like this:</p>
1261 poll mainsite.example.com proto pop3 user ....
1262 poll secondary.example.com proto pop3 interval 6 user ...
1265 <p>Then secondary.example.com will be polled every 6th time that
1266 mainsite.example.com is polled, which with a polling interval of
1267 every 5 minutes means that secondary.example.com will be polled
1268 every 30 minutes.</p>
1271 <h2><a id="C6" name="C6">Fetchmail works OK started up manually,
1272 but not from an init script.</a></h2>
1274 <p>Often, startup scripts have a different environment than an
1275 interactive login shell. For instance, $HOME might point to "/root"
1276 when you are logged in as root, but it might be either unset, or
1277 set to "/" when the startup scripts are running. That means
1278 fetchmail at startup can't find the .fetchmailrc.</p>
1280 <p>Pick a location (such as /etc/fetchmailrc) and use fetchmail's
1281 -f option to point fetchmail at it. That should solve the
1285 <h2><a id="C7" name="C7">C7. How can I forward mail to another
1288 <p>To forward mail to a host other than the one you are running
1289 fetchmail on, use the <code>smtphost</code> or
1290 <code>smtpname</code> option. See the manual page for details.</p>
1293 <h2><a id="T1" name="T1">T1. How can I use fetchmail with
1296 <p>For most sendmails, no special configuration is required. Eric
1297 Allman tells me that if <code>FEATURE(always_add_domain)</code> is
1298 included in sendmail's configuration, you can leave the
1299 <code>rewrite</code> option off.</p>
1301 <p>If your sendmail complains ``sendmail does not relay'', make
1302 sure your sendmail.cf file says <code>Cwlocalhost</code> so that
1303 sendmail recognizes `localhost' as a name of its host.</p>
1305 <p>If you're mailing from another machine on your local network,
1306 also ensure that its IP address is listed in ip_allow or name in
1307 name_allow (usually in /etc/mail/)</p>
1309 <p>If you find that your sendmail doesn't like the address
1310 `FETCHMAIL-DAEMON@localhost' (which is used in the bouncemail that
1311 fetchmail generates), you may have to set
1312 <code>FEATURE(accept_unqualified_senders)</code>.</p>
1314 <p>Günther Leber reports that Digital Unix sendmails won't
1315 work with fetchmail. The symptom is an error message "<code>553
1316 Local configuration error, hostname not recognized as
1317 local</code>". The problem is that fetchmail normally feeds
1318 sendmail with the client machine's host address in the MAIL FROM
1319 line. These sendmails think this means they're seeing the result of
1320 a mail loop and suppress the mail. You may be able to work around
1321 this by running in <code>--invisible</code> mode.</p>
1323 <p>If you want to support multidrop mode, and you can get access to
1324 your mailserver's sendmail.cf file, it's a good idea to add this
1328 H?l?Delivered-To: $h
1331 <p>This will cause the mailserver's sendmail to reliably write the
1332 appropriate envelope address into each message before fetchmail
1333 sees it, and tell fetchmail which header it is.  With this
1334 change, multidrop mode should work reliably even when the Received
1335 header omits the envelope address (which will typically be the case
1336 when the message has multiple recipients).  However it will
1337 still not distinguish the recipients, your only advantage is that
1338 no bounce will be sent if a message is BCC addressed to multiple
1339 users at your site.  To fix even that problem, you might want
1340 to try the following hack, which is however untested and quite
1344 H?J?Delivered-To: $u
1346 Mmdrop, P=/usr/bin/procmail, F=lsDFMqSPfhnu9J,
1347 S=EnvFromSMTP/HdrFromSMTP, R=EnvToSMTP/HdrToSMTP,
1348 T=DNS/RFC822/X-Unix,
1349 A=procmail -Y -a $u -d $h
1352 <p>For both hacks, you have to declare `<code>envelope
1353 "Delivered-To:"</code>' on the fetchmail side, to put the virtual
1354 domain (e.g. `domain.com') with RELAY permission into your access
1355 file and to add a line reading `<code>domain.com
1356 local:local-pop-user</code>' for the first and `<code>domain.com
1357 mdrop:local-pop-user</code>' for the second hack to your
1360 <p>You will notice that if the mail already has a Delivered-To
1361 header, sendmail will not add another.  Further, editing
1362 sendmail.cf directly is not very comfortable.  Solutions for
1363 both problems can be found in Peter `Rattacresh' Backes' `hybrid'
1364 patch against sendmail.  Have a look at it, you can find it in
1365 the contrib subdirectory.</p>
1367 <p>Feel free to try Martijn Lievaart's detailed recipe in the
1368 contrib subdirectory of the fetchmail source distribution, it
1369 attempts to realize multidrop mailboxes with an external
1372 <p>If for some reason you are invoking sendmail via the
1373 <tt>mda</tt> option (rather than delivering to port 25 via smtp),
1374 don't forget to include the -i switch. Otherwise you will
1375 occasionally get mysterious delivery failures with a SIGPIPE as the
1376 sendmail instance dies. The problem is messages with a single dot
1377 at start of a text line.</p>
1380 <h2><a id="T2" name="T2">T2. How can I use fetchmail with
1383 <p>Turn on the <code>forcecr</code> option; qmail's listener mode
1384 doesn't like header or message lines terminated with bare
1387 <p>(This information is thanks to Robert de Bath
1388 <robert@mayday.cix.co.uk>.)</p>
1390 <p>If a mailhost is using the qmail package (see <a
1391 href="http://pobox.com/~djb/qmail.html">http://pobox.com/~djb/qmail.html</a>)
1392 then, providing the local hosts are also using qmail, it is
1393 possible to set up one fetchmail link to be reliably collect the
1394 mail for an entire domain.</p>
1396 <p>One of the basic features of qmail is the `Delivered-To:'
1397 message header. Whenever qmail delivers a message to a local
1398 mailbox it puts the username and hostname of the envelope recipient
1399 on this line. The major reason for this is to prevent mail
1402 <p>To set up qmail to batch mail for a disconnected site the
1403 ISP-mailhost will have normally put that site in its `virtualhosts'
1404 control file so it will add a prefix to all mail addresses for this
1405 site. This results in mail sent to
1406 'username@userhost.userdom.dom.com' having a 'Delivered-To:' line
1410 Delivered-To: mbox-userstr-username@userhost.userdom.dom.com
1413 <p>A single host maildrop will be slightly simpler:</p>
1416 Delivered-To: mbox-userstr-username@userhost.dom.com
1419 <p>The ISP can make the 'mbox-userstr-' prefix anything they choose
1420 but a string matching the user host name is likely.</p>
1422 <p>To use this line you must:</p>
1425 <li>Ensure the option `envelope Delivered-To:' is in the fetchmail
1428 <li>Ensure you have a localdomains containing 'userdom.dom.com' or
1429 `userhost.dom.com' respectively.</li>
1432 <p>So far this reliably delivers messages to the correct machine of
1433 the local network, to deliver to the correct user the
1434 'mbox-userstr-' prefix must be stripped off of the user name. This
1435 can be done by setting up an alias within the qmail MTA on each
1436 local machine. Simply create a dot-qmail file called
1437 '.qmail-mbox-userstr-default' in the alias directory (normally
1438 /var/qmail/alias) with the contents:</p>
1441 | ../bin/qmail-inject -a -f"$SENDER" "${LOCAL#mbox-userstr-}@$HOST"
1444 <p>Note this <em>does</em> require a modern /bin/sh.</p>
1446 <p>Peter Wilson adds:</p>
1448 <p>``My ISP uses "alias-unzzippedcom-" as the prefix, which means
1449 that I need to name my file ".qmail-unzzippedcom-default". This is
1450 due to qmail's assumption that a message sent to user-xyz is
1451 handled by the file ~user/.qmail-xyz (or
1452 ~user/.qmail-default).''</p>
1454 <p>Luca Olivetti adds:</p>
1456 <p>If you aren't using qmail locally, or you don't want to set up
1457 the alias mechanism described above, you can use the option
1458 `<code>qvirtual "mbox-userstr-"</code>' in your fetchmail config
1459 file to strip the prefix from the local user name.</p>
1462 <h2><a id="T3" name="T3">T3. How can I use fetchmail with
1465 <p>If you have <code>rewrite</code> on:</p>
1467 <p>There is an RFC1123 requirement that MAIL FROM and RCPT TO
1468 addresses you pass to it have to be canonical (e.g. with a fully
1469 qualified hostname part). Therefore fetchmail tries to pass fully
1470 qualified RCPT TO addresses. But exim does not by default accept
1471 `localhost' as a fully qualified domain. This can be fixed.</p>
1473 <p>In exim.conf, add `localhost' to your local_domains declaration
1474 if it's not already present. For example, the author's site at
1475 thyrsus.com would have a line reading:</p>
1478 local_domains = thyrsus.com:localhost
1481 <p>If you have <code>rewrite</code> off:</p>
1483 <p>MAIL FROM is a potential problem if the MTAs upstream from your
1484 fetchmail don't necessarily pass canonicalized From and Return-Path
1485 addresses, and fetchmail's <code>rewrite</code> option is off. The
1486 specific case where this has come up involves bounce messages
1487 generated by sendmail on your mailer host, which have the
1488 (un-canonicalized) origin address MAILER-DAEMON.</p>
1490 <p>The right way to fix this is to enable the <code>rewrite</code>
1491 option and have fetchmail canonicalize From and Return-Path
1492 addresses with the mailserver hostname before exim sees them. This
1493 option is enabled by default, so it won't be off unless you turned
1496 <p>If you must run with <code>rewrite</code> off, there is a switch
1497 in exim's configuration files that allows it to accept domainless
1498 MAIL FROM addresses; you will have to flip it by putting the
1502 sender_unqualified_hosts = localhost
1505 <p>in the main section of the exim configuration file. Note that
1506 this will result in such messages having an incorrect domain name
1507 attached to their return address (your SMTP listener's hostname
1508 rather than that of the remote mail server).</p>
1511 <h2><a id="T4" name="T4">T4. How can I use fetchmail with
1514 <p>Smail 3.2 is very nearly plug-compatible with sendmail, and may
1515 work fine out of the box.</p>
1517 <p>We have one report that when processing multiple messages from a
1518 single fetchmail session, smail sometimes delivers them in an order
1519 other than received-date order. This can be annoying because it
1520 scrambles conversational threads. This is not fetchmail's problem,
1521 it is an smail `feature' and has been reported to the maintainers
1524 <p>Very recent smail versions require an
1525 <code>-smtp_hello_verify</code> option in the smail config file.
1526 This overrides smail's check to see that the HELO address is
1527 actually that of the client machine, which is never going to be the
1528 case when fetchmail is in the picture. According to RFC1123 an SMTP
1529 listener <em>must</em> allow this mismatch, so smail's new behavior
1530 (introduced sometime between 3.2.0.90 and 3.2.0.95) is a bug.</p>
1532 <p>You may also need to say
1533 <code>-smtp_hello_broken_allow=127.0.0.1</code> in order for smail
1534 to accept the "localhost" that fetchmail normally appends to
1535 recipient addresses.</p>
1538 <h2><a id="T5" name="T5">T5. How can I use fetchmail with SCO's
1541 <p>MMDF itself is difficult to configure, but it turns out that
1542 connecting fetchmail to MMDF's SMTP channel isn't that hard. You
1544 href="http://www.aplawrence.com/Unixart/uucptofetch.html">MMDF
1545 recipe</a> that describes replacing a UUCP link with fetchmail
1549 <h2><a id="T6" name="T6">T6. How can I use fetchmail with Lotus
1552 <p>The Lotus Notes SMTP gateway tries to deduce when it should
1553 convert \n to \r\n, but its rules are not the intuitive and
1554 correct-for-RFC822 ones. Use `forcecr'.</p>
1557 <h2><a id="T7" name="T7">T7. How can I use fetchmail with Courier
1560 <p>The courier mta doesn't like RCPT addresses that look like
1561 <code>someone@localhost</code>. Work around this with an
1562 <code>smtphost</code> or <code>smtpaddress</code>.</p>
1565 <h2><a name="T8">T8. How can I use fetchmail with vbmailshield?</a></h2>
1567 <p>vbmailshield's SMTP interpreter is broken. It doesn't understand RSET.</p>
1569 <p>As a workaround, you can set batchlimit to 1 so RSET is never used.</p>
1572 <h2><a id="S1" name="S1">S1. How can I use fetchmail with
1575 <p>Qualcomm's qpopper is probably the best-of-breed among POP3
1576 servers, and is very widely deployed. Nevertheless, it has some
1577 problems which fetchmail exposes. We recommend using <a
1578 href="#G8">IMAP</a> instead if at all possible. If you must talk to
1579 qpopper, here are some problems to be aware of:</p>
1581 <h3>Problems with retrieving large messages from qpopper 2.53</h3>
1584 href="mailto:tony@atn.com.hk"><tony@atn.com.hk></a> reports
1585 that there is a bad intercation between fetchmail and qpopper 2.5.3
1586 under Red Hat Linux versions 5.0 to 5.2, kernels 2.0.34 to 2.0.35.
1587 When fetching very large messages (over 700K) from 2.5.3, fetchmail
1588 will hang with a socket error.</p>
1590 <p>This is probably not a fetchmail bug, but rather a symptom of
1591 some problem in the networking stack that qpopper's transmission
1592 pattern is tickling, as fetchpop (another Linux POP client) also
1593 displays the hang but Netscape running under Win95 does not. The
1594 problem can also be banished by <a
1595 href="http://www.eudora.com/freeware/qpop.html">upgrading to
1596 qpopper 3.0b1</a>.</p>
1598 <h3>Bad interaction with fetchmail 4.4.2 to 4.4.7</h3>
1600 <p>Versions of fetchmail from 4.4.2 through 4.4.7 had a bad
1601 interaction with Eudora qpopper versions 2.3 and later. See <a
1602 href="#X5">X5</a> for details. The solution is to upgrade your
1606 <h2><a id="S2" name="S2">S2. How can I use fetchmail with Microsoft
1609 <p>It's been reliably reported that Exchange 2000's POP3 support is
1610 so broken that it's unusable. One symptom is that messages without
1611 a terminating newline get the POP3 message termination dot emitted
1612 -- you guessed it -- right after the last character of the message,
1613 with no terminating newline added. This will hang fetchmail or any
1614 other RFC-compliant server. IMAP is alleged to work OK, though.</p>
1616 <p>Older versions of Exchange are semi-usable. They randomly drop
1617 attachments on the floor, though. Microsoft acknowledges this
1618 as a known bug and apparently has no plans to fix it.</p>
1620 <p>Fetchmail using IMAP supports the proprietary NTLM mode used
1621 with M$ Exchange servers. To enable this, configure fetchmail with
1622 the --enable-NTLM option and recompile it. Specify a user option
1623 value that looks like `user@domain': the part to the left of the @
1624 will be passed as the username and the part to the right as the
1627 <p>M$ Exchange violates the POP3 and IMAP RFCs. Its LIST command
1628 does not reveal the real sizes of mail in the pop mailbox, but the
1629 sizes of the compressed versions in the exchange mail database
1630 (thanks to Arjan De Vet and Guido Van Rooij for alerting us to this
1633 <p>Fetchmail works with M$ Exchange, despite this brain damage. Two
1634 features are compromised. One is that the --limit option will not
1635 work right (it will check against compressed and not actual sizes).
1636 The other is that a too-small SIZE argument may be passed to your
1637 ESMTP listener, assuming you're using one (this should not be a
1638 problem unless the actual size of the message is above the
1639 listener's configured length limit).</p>
1641 <p>Somewhat belatedly, I've learned that there's supposed to be a
1642 registry bit that can fix this breakage:</p>
1645 HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MsExchangeIs\Parameters
1646 System\Pop3 Compatibility
1649 <p>This is a bitmask that controls the variations from the standard
1650 protocol. The bits defined are:</p>
1653 <dt>0x00000001:</dt>
1655 <dd>Report exact message sizes for the LIST command</dd>
1657 <dt>0x00000002:</dt>
1659 <dd>Allow arbitrary linear whitespace between commands and
1662 <dt>0x00000004:</dt>
1664 <dd>Enable the LAST command</dd>
1666 <dt>0x00000008:</dt>
1668 <dd>Allow an empty PASS command (needed for users with blank
1669 passwords, but illegal in the protocol)</dd>
1671 <dt>0x00000010:</dt>
1673 <dd>Relax the length restrictions for arguments to commands
1674 (protocol requires 40, but some user names may be longer than
1677 <dt>0x00000020:</dt>
1679 <dd>Allow spaces in the argument to the USER command.</dd>
1682 <p>There's another one that may be useful to know about:</p>
1685 KEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MsExchangeIs\Parameters
1686 System\Pop3 Performance
1690 <dt>0x00000001:</dt>
1692 <dd>Render messages to a temporary stream instead of sending
1693 directly from the database (should always be on)</dd>
1695 <dt>0x00000002: Flag unrenderable messages (instead of just failing
1696 commands) (should only be on if you are seeing the problems
1697 reported in KB Q168109)</dt>
1699 <dt>0x00000004:</dt>
1701 <dd>Return from the QUIT command before all messages have been
1705 <p>The Microsoft pod-person who revealed this information to me
1706 admitted that he couldn't find it anywhere in their public
1709 <p>Another specific problem we have seen with Exchange servers has
1710 as its symptom a response to LOGIN that says "NO Ambiguous Alias".
1711 Grant Edwards writes:</p>
1713 <p>This means that Exchange Server is too f*&#ing stupid to
1714 figure out which mailbox belongs to you. Instead of actually
1715 keeping track of which inbox belongs to which user, it uses some
1716 half-witted, guess-o-matic heuristic to try to guess your mailbox
1717 name from your username.</p>
1719 <p>In your case it doesn't work because your username maps to more
1720 than one mailbox. For some people it doesn't work because their
1721 username maps to zero mailboxes. This is yet another inept, lame,
1722 almost criminally negligent design decision from our friends in
1725 <p>You've got several options:</p>
1728 <li>Get your administrator to configure the server so that
1729 usernames and mailbox names are the same.</li>
1731 <li>Get your administrator to add an alias that maps your username
1732 explicitly to your mailbox name.</li>
1735 <p>But, the best option involves a tactical nuclear weapon (an old
1736 ASROC will do), pissing off a lot people who live downwind from
1737 Redmond, and your choice of any Linux, NetBSD, FreeBSD, or Solaris
1741 <h2><a id="S3" name="S3">S3. How can I use fetchmail with HP
1744 <p>No special configuration is required, but OpenMail versions
1745 prior to 6.0 have an annoying bug similar to the big one in <a
1746 href="#S2">Microsoft Exchange</a>. The message sizes it gives in
1747 the LIST are rounded to the nearest 1024 bytes. It also has a nasty
1748 habit of discarding headers it doesn't recognize, such as X- and
1749 Resent- headers.</p>
1751 <p>As with M$ Exchange, the only real fix for these problems is to
1752 get a POP (or preferably IMAP) server that isn't brain-dead.
1753 OpenMail's project manager claims these bugs have been fixed in
1756 <p>We've had a more recent report (December 2001) that the TOP
1757 command fails, returning only one line regrardless of its argument,
1758 on something identifying itself as "OpenMail POP3 interface".</p>
1761 <h2><a id="S4" name="S4">S4. How can I use fetchmail with Novell GroupWise?</a></h2>
1763 <p>The Novell GroupWise IMAP server would be better named
1764 GroupFoolish; it is (according to the designer of IMAP) unusably
1765 broken. Among other things, it doesn't include a required content
1766 length in its BODY[TEXT] response.</p>
1768 <p>Fetchmail works around this problem, but we strongly recommend
1769 voting with your dollars for a server that isn't brain-dead. If you
1770 stick with code as shoddy as GroupWise seems to be, you will
1771 probably pay for it with other problems.</p>
1774 <h2><a id="S5" name="S5">S5. How can I use fetchmail with
1775 InterChange?</a></h2>
1777 <p>You can't. At least not if you want to be able to see
1778 attachments. InterChange has a bug similar to the MailMax server;
1779 it reports the message length with attachments but doesn't download
1780 them on TOP or RETR.</p>
1782 <p>On Jan 9 2001, the people at InfiniteMail sent me mail informing
1783 me that their new 3.61.08 release of InterChange fixes this
1784 problem. I don't have any reports one way or the other yet.</p>
1787 <h2><a id="S6" name="S6">S6. How can I use fetchmail with MailMax?</a></h2>
1789 <p>You can't. At least not if you want to be able to see
1790 attachments. MailMax has a bug; it reports the message length with
1791 attachments but doesn't download them on TOP or RETR.</p>
1793 <p>Also, we're told that TOP sometimes fails to retrieve the entire
1794 message even when enough lines have been specified. The MailMax
1795 developers have acknowledged this bug as of 4 May 2000, but there
1796 is no fix yet. If you must use this server, force RETR with the
1797 <tt>fetchall</tt> option.</p>
1800 <h2><a id="S7" name="S7">S7. How can I use fetchmail with FTGate?</a></h2>
1802 <p>The FTGate V2 server (and possibly older versions as well) has a
1803 weird bug. It answers OK twice to a TOP request! Use the
1804 <code>fetchall</code> option to force use of RETR and work around
1808 <h2><a id="I1" name="I1">I1. How can I use fetchmail with CompuServe RPA?</a></h2>
1810 <p>First, make sure your fetchmail has the RPA support compiled in.
1811 Stock fetchmail binaries (such as you might get from an RPM) don't.
1812 You can check this by looking at the output of <code>fetchmail
1813 -V</code>; if you see the string "+RPA" after the version ID you're
1814 good to go, otherwise you'll have to build your own from sources
1815 (see the INSTALL file in the source distribution for
1818 <p>Give your CompuServe pass-phrase in lower case as your password.
1819 Add `@compuserve.com' to your user ID so that it looks like `user
1820 <UserID>@compuserve.com', where <UserID> can be either
1821 your numerical userID or your E-mail nickname. An RPA-enabled
1822 fetchmail will automatically check for csi.com in the POP server's
1823 greeting line. If that's found, and your user ID ends with
1824 `@compuserve.com', it will query the server to see if it is
1825 RPA-capable, and if so do an RPA transaction rather than a
1826 plain-text password handshake.</p>
1828 <p><strong>Warning:</strong> the debug (-v -v) output of fetchmail
1829 will show your pass-phrase in Unicode!</p>
1831 <p>These two .fetchmailrc entries show the difference between an
1832 RPA and non-RPA configuration:</p>
1835 # This version will use RPA
1836 poll csi.com via "pop.site1.csi.com" with proto POP3 and options no dns
1837 user "CSERVE_USER@compuserve.com" there with password "CSERVE_PASSWORD"
1838 is LOCAL_USER here options fetchall stripcr
1840 # This version will not use RPA
1841 poll non-rpa.csi.com via "pop.site1.csi.com" with proto POP3 and options no dns
1842 user "CSERVE_USER" there with password "CSERVE_POP3_PASSWORD"
1843 is LOCAL_USER here options fetchall stripcr
1847 <h2><a id="I2" name="I2">I2. How can I use fetchmail with Demon
1848 Internet's SDPS?</a></h2>
1850 <h3>Single-drop mode</h3>
1852 <p>You can get fetchmail to download the email for just one user
1853 from Demon Internet's POP3 server by giving it a username
1854 consisting of your Demon user name followed by your account name,
1855 with an at-sign between them.</p>
1857 <p>For example, to download email for the user
1858 <philh@vision25.demon.co.uk>, you could use the following
1859 .fetchmailrc file:</p>
1862 set postmaster "philh"
1863 poll pop3.demon.co.uk with protocol POP3:
1864 user "philh@vision25" is philh
1867 <h3>Multi-drop mode</h3>
1869 <p>Demon Internet's SDPS service is an implementation of POP3. All
1870 messages have a Received: header added when they enter the
1871 maildrop, like this:</p>
1874 Received: from punt-1.mail.demon.net by mailstore for fred@xyz.demon.co.uk
1875 id 899963657:10:27896:0; Thu, 09 Jul 98 05:54:17 GMT
1878 <p>To enable multi-drop mode you need to tell fetchmail that
1879 'mailstore' is the name of the host which accepted the mail, and
1880 let it know the hostname part(s) of your E-mail address. The
1881 following example assumes that your hostname is xyz.demon.co.uk,
1882 and that you have also bought "mail forwarding" for the domain
1883 my-company.co.uk (in which case your MTA must also be configured to
1884 accept mail sent to user@my-company.co.uk)</p>
1887 poll pop3.demon.co.uk proto pop3 aka mailstore no dns:
1888 localdomains xyz.demon.co.uk my-company.co.uk
1892 <p>Note that Demon may delete mail on the server which is more than
1893 30 days old; see their <a
1894 href="http://www.demon.net/helpdesk/products/mail/sdps-tech.shtml">POP3
1895 page</a> for details.</p>
1897 <h3>The SDPS extension</h3>
1899 <p>There's a different way to do multidrop. It's not necessary on
1900 Demon Internet, since fetchmail can parse Received addresses, but
1901 the person who implemented this didn't know that. It may be useful
1902 if Demon Internet ever changes mail transports.</p>
1904 <p>SDPS includes a non-standard extension for retrieving the
1905 envelope of a message (*ENV), which fetchmail optionally supports
1906 if compiled with the --enable-SDPS option. If you have it, the
1907 first line of the fetchmail -V response will include the string
1910 <p>Once you have SDPS compiled in, fetchmail in POP3 mode will
1911 automatically detect when it's talking to a Demon Internet host in
1912 multidrop mode, and use the *ENV extension to get an envelope To
1915 <p>The autodetection works by looking at the hostname in the POP3
1916 greeting line; if you're accessing Demon Internet through a proxy
1917 it may fail. To force SDPS mode, pick "sdps" as your protocol.</p>
1920 <h2><a id="I3" name="I3">I3. How can I use fetchmail with usa.net's
1923 <p>Enable `<code>fetchall</code>'. A user reports that the 2.2
1924 version of USA.NET's POP server reports that you must use the
1925 `<code>fetchall</code>' option to make sure that all of the mail is
1926 retrieved, otherwise some may be left on the server. This is almost
1927 certainly a server bug.</p>
1929 <p>The usa.net servers (at least in their 2.2 version, June 1998)
1930 don't handle the TOP command properly, either. Regardless of the
1931 argument you give it, they retrieve only about 10 lines of the
1932 message. Fetchmail normally uses TOP for message retrieval in order
1933 to avoid marking messages seen, but `<code>fetchall</code>' forces
1934 it to use RETR instead.</p>
1936 <p>Also, we're told USA.NET adds a ton of hops to your messages.
1937 You may need to raise the MaxHopCount parameter in your sendmail.cf
1938 to avoid having fetched mail rejected.</p>
1940 <p>(Note: Other failure modes have been reported on usa.net's
1941 servers. They seem to be chronically flaky. We recommend finding
1942 another provider.)</p>
1945 <h2><a id="I4" name="I4">I4. How can I use fetchmail with geocities
1946 POP3 servers?</a></h2>
1948 <p>Nathan Cutler reports that the the mail.geocities.com POP3
1949 servers fail to include the first Received line of the message in
1950 the send to fetchmail. This can solve problems if your MUA
1951 interprets Received continuations as body lines and doesn't parse
1952 any of the following headers.</p>
1954 <p>Workaround is to use "mda" keyword or "-mda" switch:</p>
1957 mda "sed -e '1s/^\t/Received: /' | formail | /usr/bin/procmail -d <user>"
1960 <p>Replace \t with exactly one tabulation character.</p>
1962 <p>You should also consider using "fetchall" option because
1963 Geocities' servers sometimes think that the first 45 messages have
1964 already been read.</p>
1966 <p>Fix: Get an email provider that doesn't suck. The pop-up ads on
1967 Geocities are lame, you should boycott them anyway.</p>
1970 <h2><a id="I5" name="I5">I5. How can I use fetchmail with Hotmail?</a></h2>
1972 <p>You can't, yet. But <a
1973 href="http://linux.cudeso.be/linuxdoc/gotmail.php">gotmail</a> or
1974 <a href='http://people.freenet.de/courierdave/'>HotWayDaemon</a> might
1975 be what you need.</p>
1978 <h2><a id="I6" name="I6">I6. How can I use fetchmail with MSN?</a></h2>
1980 <p>You can't. MSN uses something that looks like POP3, except the
1981 authentication part is nonstandard. And of course they don't
1982 document it, so nobody but their Windows clients can speak it.</p>
1984 <p>This is a customer lock-in tactic; we recommend boycotting MSN
1985 as the only appropriate response.</p>
1987 <p>As of 5.0.8, we have support for the client side of NTLM
1988 authentication. It's possible this may enable fetchmail to talk to
1989 MSN; if so, somebody should report it so this FAQ can be
1993 <h2><a id="I7" name="I7">I7. How can I use fetchmail with SpryNet?</a></h2>
1995 <p>The SpryNet POP3 servers mark a message queried with TOP as
1996 seen. This means that if your connection drops in mid-message, it
1997 may end up invisibly stuck on your mail spool. Use the
1998 <code>fetchall</code> flag to ensure that it's recovered on the
2002 <h2><a id="I8" name="I8">I8. How can I use fetchmail with comcast.net?</a></h2>
2004 <p>Stock fetchmail will work with a comcast.net server...<em>but</em>
2005 the Maillennium POP3 server comcat uses seems to have an 80K limit on
2006 the length of downloaded messages if you use POP3 TOP to retrieve.
2007 Anything larger is silently truncated. Don't mistake this for a
2008 fetchmail bug. (Reported July 2003.)</p>
2010 <p>Workaround: use the <tt>fetchall</tt> option.</p>
2013 <h2><a id="K1" name="K1">K1. How can I use fetchmail with SOCKS?</a></h2>
2015 <p>Giuseppe Guerini added a --with-socks option that supports
2016 linking with socks library. If you specify the value of this option
2017 as ``yes'', the configure script will try to find the Rconnect
2018 library and set the makefile up to link it. You can also specify a
2019 directory containing the Rconnect library.</p>
2021 <p>Alan Schmitt has added a similar --with-socks5 option that may
2022 work better if you have a recent version of the SOCKS library.</p>
2025 <h2><a id="K2" name="K2">K2. How can I use fetchmail with IPv6 and
2028 <p>To use fetchmail with IPv6, you need a system that supports
2029 IPv6, the "Basic Socket Interface Extensions for IPv6" (RFC 2133).
2030 This currently means that you need to have a BSD/OS or NetBSD
2031 system with the NRL IPv6+IPsec software distribution or a Linux
2032 system with a 2.2 or later kernel and net-tools. It should not be
2033 hard to build fetchmail on other IPv6 implementations if you can
2034 port the inet6-apps kit.</p>
2036 <p>To use fetchmail with networking security (read: IPsec), you
2037 need a system that supports IPsec, the API described in the
2038 "Network Security API for Sockets"
2039 (draft-metz-net-security-api-01.txt), and the inet6-apps kit. This
2040 currently means that you need to have a BSD/OS or NetBSD system
2041 with the NRL IPv6+IPsec software distribution. A Linux IPsec
2042 implementation supporting this API will probably appear in the
2045 <p>The NRL IPv6+IPsec software distribution can be obtained from:
2047 href="http://web.mit.edu/network/isakmp">http://web.mit.edu/network/isakmp</a></p>
2049 <p>The inet6-apps kit can be obtained from <a
2050 href="http://ftp.ps.pl/pub/linux/IPv6/inet6-apps/">http://ftp.ps.pl/pub/linux/IPv6/inet6-apps/</a>.</p>
2052 <p>More information on using IPv6 with Linux can be obtained
2057 href="http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO.html">
2058 http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO.html</a></li>
2061 href="http://www.ipv6.inner.net/ipv6">http://www.ipv6.inner.net/ipv6</a>
2065 href="http://www.inner.net/ipv6">http://www.inner.net/ipv6</a> (via
2070 <h2><a id="K3" name="K3">K3. How can I get fetchmail to work with
2073 <p>Use the <tt>plugin</tt> option. This is dead simple with
2077 plugin "ssh %h /usr/sbin/imapd"
2080 <p>You may have to use a different absolute pathname, whatever the
2081 location of imapd on your mailserver is. This option tells
2082 fetchmail that instead of opening a connection on the server's port
2083 143 and doing standard IMAP authentication, fetchmail should ssh to
2084 the server and run imapd, using the more secure ssh authentication
2085 (as well as getting ssh's end-to-end encryption). Most IMAP daemons
2086 will detect that they've been called from the command line and
2087 assume the connection is preauthenticated.</p>
2089 <p>POP3 daemons aren't quite as smart. They won't know they are
2090 preauthenticated in this mode, so you'll actually have to ship your
2091 password. It will be under ssh encryption, though, so that
2092 shouldn't be a problem.</p>
2095 <h2><a id="K4" name="K4">K4. What do I have to do to use the
2096 IMAP-GSS protocol?</a></h2>
2098 <p>Fetchmail can use RFC1731 GSSAPI authorization to safely
2099 identify you to your IMAP server, as long as you can share Kerberos
2100 V credentials with your mail host and you have a GSSAPI-capable
2101 IMAP server. UW-IMAP (available via FTP at <a
2102 href="ftp://ftp.cac.washington.edu/mail/">ftp.cac.washington.edu</a>)
2103 is the only one I'm aware of and the one I recommend anyway for
2104 other reasons. You'll need version 4.1-FINAL or greater though, and
2105 it has to have GSS support compiled in.</p>
2107 <p>Neither UW-IMAP nor fetchmail compile in support for GSS by
2108 default, since it requires libraries from the Kerberos V
2109 distribution (available via FTP at <a
2110 href="ftp://athena-dist.mit.edu/pub/ATHENA/kerberos">athena-dist.mit.edu</a>).
2111 If you have these, compiling in GSS support is simple: add a
2112 <code>--with-gssapi=[/path/to/krb5/root]</code> option to
2113 configure. For instance, I have all of my Kerberos V libraries
2114 installed under /usr/krb5 so I run <code>configure
2115 --with-gssapi=/usr/krb5</code></p>
2117 <p>Setting up Kerberos V authentication is beyond the scope of this
2118 FAQ (you may find Jim Rome's paper <a
2119 href="http://www.ornl.gov/~jar/HowToKerb.html">How to Kerberize
2120 your site</a> helpful), but you'll at least need to add a
2121 credential for imap/[mailhost] to the keytab of the mail server
2122 (IMAP doesn't just use the host key). Then you'll need to have your
2123 credentials ready on your machine (cf. kinit).</p>
2125 <p>After that things are very simple. Set your protocol to imap-gss
2126 in your .fetchmailrc, and omit the password, since imap-gss doesn't
2127 need one. You can specify a username if you want, but this is only
2128 useful if your mailbox belongs to a username different from your
2129 Kerberos principal.</p>
2131 <p>Now you don't have to worry about your password appearing in
2132 cleartext in your .fetchmailrc, or across the network.</p>
2135 <h2><a id="K5" name="K5">K5. How can I use fetchmail with
2138 <p>You'll need to have the <a
2139 href="http://www.openssl.org/">OpenSSL</a> libraries installed.
2140 Configure with --with-ssl. If you have the OpenSSL libraries
2141 installed in the default location (/usr/local/ssl) ths will
2142 suffice. If you have them installed in a non-default location,
2143 you'll need to specify it as an argument to --with-ssl after an
2146 <p>Note that there is a known bug in the implementation of SSL_peek
2147 under OpenSSL versions 0.9.5 and older that fetchmail occasionally
2148 tripped over, causing hangs. It is recommended that you install
2151 <p>Fetchmail binaries built this way support <code>ssl</code>,
2152 <code>sslkey</code>, and <code>sslcert</code> options that control
2153 SSL encryption. You will need to have an SSL-enabled mailserver to
2154 use these options. See the manual page for details and some words
2155 of care on the limited security provided.</p>
2157 <p>If your open OpenSSL session dies with a message that complains
2158 "PRNG not seeded", update or improve your operating system. This
2159 means that the OpenSSL library on your machine has been unable to
2160 locate a source of random bits from which to seed its random-number
2161 generator; normally these come from the <tt>/dev/urandom</tt>, and
2162 this message probably means your OS doesn't have that device.</p>
2164 <p>An interactive program could seed the random number generator
2165 from keystroke timings or some other form of user input. Because
2166 fetchmail is primarily designed to run forever as a background
2167 daemon, that option is not available in this case.</p>
2169 <p>If you don't have the libraries installed, but do have the
2170 OpenSSL utility toolkit, something like this may work:</p>
2173 poll MYSERVER port 993 plugin "openssl s_client -connect %h:%p"
2174 protocol imap username MYUSERNAME password MYPASSWORD
2178 <h2><a id="R1" name="R1">R1. Fetchmail isn't working, and -v shows
2179 `SMTP connect failed' messages.</a></h2>
2181 <p>Fetchmail itself is probably working, but your SMTP port 25
2182 listener is down or inaccessible.</p>
2184 <p>The first thing to check is if you can telnet to port 25 on your
2185 smtp host (which is normally `localhost' unless you've specified an
2186 smtp option in your .fetchmailrc or on the command line) and get a
2187 greeting line from the listener. If the SMTP host is inaccessible
2188 or the listener is down, fix that first.</p>
2190 <p>In Red Hat Linux 6.x, SMTP is disabled by default. To fix this,
2191 set "DAEMON=yes" in your /etc/sysconfig/sendmail file, then restart
2192 sendmail by running "/sbin/service sendmail restart".</p>
2194 <p>If the listener seems to be up when you test with telnet, the
2195 most benign and typical problem is that the listener had a
2196 momentary seizure due to resource exhaustion while fetchmail was
2197 polling it -- process table full or some other problem that stopped
2198 the listener process from forking. If your SMTP host is not
2199 `localhost' or something else in /etc/hosts, the fetchmail glitch
2200 could also have been caused by transient nameserver failure.</p>
2202 <p>Try running fetchmail -v again; if it succeeds, you had one of
2203 these kinds of transient glitch. You can ignore these hiccups,
2204 because a future fetchmail run will get the mail through.</p>
2206 <p>If the listener tests up, but you have chronic failures trying
2207 to connect to it anyway, your problem is more serious. One way to
2208 work around chronic SMTP connect problems is to use --mda. But this
2209 only attacks the symptom; you may have a DNS or TCP routing
2210 problem. You should really try to figure out what's going on
2211 underneath before it bites you some other way.</p>
2213 <p>We have one report (from toby@eskimo.com) that you can sometimes
2214 solve such problems by doing an <code>smtp</code> declaration with
2215 an IP address that your routing table maps to something other than
2216 the loopback device (he used ppp0).</p>
2218 <p>We also have a report that this error can be caused by having an
2219 /etc/hosts file that associates your client host name with more
2220 than one IP address.</p>
2222 <p>It's also possible that your DNS configuration isn't looking at
2223 <code>/etc/hosts</code> at all. If you're using libc5, look at
2224 <code>/etc/resolv.conf</code>; it should say something like:</p>
2230 <p>so your <code>/etc/hosts</code> file is checked first. If you're
2231 running GNU libc6, check your <code>/etc/nsswitch.conf</code> file.
2232 Make sure it says something like</p>
2238 <p>again, in order to make sure <code>/etc/hosts</code> is seen
2241 <p>If you have a hostname set for your machine, and this hostname
2242 does not appear in /etc/hosts, you will be able to telnet to port
2243 25 and even send a mail with rcpt to: user@host-not-in-/etc/hosts,
2244 but fetchmail can't seem to get in touch with sendmail, no matter
2245 what you set smtpaddress to.</p>
2247 <p>We had another report from a Linux user of fetchmail 2.1 who
2248 solved his SMTP connection problem by removing the reference to
2249 -lresolv from his link line and relinking. Apparently in some older
2250 Linux distributions the libc bind library version works better.</p>
2252 <p>As of 2.2, the configure script has been hacked so the bind
2253 library is linked only if it is actually needed. So under Linux it
2254 won't be, and this particular cause should go away.</p>
2257 <h2><a id="R2" name="R2">R2. When I try to configure an MDA,
2258 fetchmail doesn't work.</a></h2>
2260 <p>(I hear this one from people who have run into the blank-line
2261 problem in <a href="#X1">X1</a>.)</p>
2263 <p>Try sending yourself test mail and retrieving it using the
2264 command-line options `<code>-k -m cat</code>'. This will dump
2265 exactly what fetchmail retrieves to standard output (plus the
2266 Received line fetchmail itself adds to the headers).</p>
2268 <p>If the dump doesn't match what shows up in your mailbox when you
2269 configure an MDA, your MDA is mangling the message. If it doesn't
2270 match what you sent, then fetchmail or something on the server is
2274 <h2><a id="R3" name="R3">R3. Fetchmail dumps core when given an
2275 invalid rc file.</a></h2>
2277 <p>This is usually reported from AIX or Ultrix, but has even been
2278 known to happen on Linuxes without a recent version of
2279 <code>flex</code> installed. The problem appears to be a result of
2280 building with an archaic version of lex.</p>
2282 <p>Workaround: fix the syntax of your .fetchmailrc file.</p>
2284 <p>Fix: build and install the latest version of <a
2285 href="ftp://prep.ai.mit.edu/~ftp/pub/gnu">flex</a> from the Free
2286 Software Foundation. An FSF <a
2287 href="http://www.gnu.ai.mit.edu/order/ftp.html">mirror site</a>
2288 will help you get it faster.</p>
2291 <h2><a id="R4" name="R4">R4. Fetchmail dumps core in -V mode, but
2292 operates normally otherwise.</a></h2>
2294 <p>We've had this reported to us under Linux using libc-5.4.17 and
2295 gcc-2.7.2. It does not occur with libc-5.3.12 or earlier
2298 <p>Workaround: link with GNU malloc rather than the stock C library
2301 <p>We're told there is some problem with the malloc() code in that
2302 version which makes it fragile in the presence of multiple free()
2303 calls on the same pointer (the malloc arena gets corrupted).
2304 Unfortunately it appears from doing gdb traces that whatever free()
2305 calls producing the problem are being made by the C library itself,
2306 not the fetchmail code (they're all from within fclose, and not an
2307 fclose called directly by fetchmail, either).</p>
2310 <h2><a id="R5" name="R5">R5. Running fetchmail in daemon mode
2311 doesn't work.</a><br/>
2314 <p>We have one report from a SunOS 4.1.4 user that trying to run
2315 fetchmail in detached daemon mode doesn't work, but that using the
2316 same options with -N (nodetach) is OK. We have another report of
2317 similar behavior from one Linux user, but many other Linux users
2318 reportt no problem.</p>
2320 <p>If this happens, you have a specific portability problem with
2321 the code in daemon.c that detaches and backgrounds the daemon
2322 fetchmail. The isolated Linux case has been chased down to a
2323 failure in dup(2) that may reflect a glibc bug.</p>
2325 <p>As a workaround, you can start fetchmail with -N and an
2326 ampersand to background it. A Sun user recommends this:</p>
2329 (fetchmail --nodetach <other params> &)
2332 <p>The extra pair of parens is significant --- it makes sure that
2333 the process detaches from the initial shell (one more shell is
2334 started and dies immediately, detaching fetchmail and making it
2335 child of PID 1). This is important when you start fetchmail
2336 interactively and than quit interactive shell. The line above makes
2337 sure fetchmail lives after that!</p>
2340 <h2><a id="R6" name="R6">R6. Fetchmail randomly dies with socket
2343 <p>Check the MTU value in your PPP interface reported by
2344 <code>/sbin/ifconfig</code>. If it's over 600, change it in your
2345 PPP options file. (<code>/etc/ppp/options</code> on my box). Here
2346 are option values that work:</p>
2353 <p>Another circumstance that can trigger this is if you are polling
2354 a virtual-mail-server name that is round-robin connected to
2355 different actual servers, so you get different IP addresses on
2356 different poll cycles. To work around this, change the poll name
2357 either to the real name of one of the servers in the ring or to a
2358 corresponding IP address.</p>
2361 <h2><a id="R7" name="R7">R7. Fetchmail running as root stopped
2362 working after an OS upgrade</a></h2>
2364 <p>In RH 6.0, the HOME value in the boot-time root environment
2365 changed from /root to / as the result of a change in init. Move
2366 your .fetchmailrc or use a -f option to explicitly point at the
2367 file. (Oddly, a similar problem has been reported from Debian
2371 <h2><a id="R8" name="R8">R8. Fetchmail is timing out after fetching
2372 certain messages but before deleting them</a></h2>
2374 <p>There's a TCP/IP stalling problem under Redhat 6.0 (and possibly
2375 other recent Linuxes) that can cause this symptom. Brian Boutel
2379 <p>TCP timestamps are turned on on my Linux boxes (I assume it's
2380 now the default). This uses 12 extra bytes per segment. When the
2381 tcp connection starts, the other end agrees a MSS of 1460, and then
2382 fragments 1460 byte chunks into 1448 and 12, because is is not
2383 allowing for the timestamp.</p>
2385 <p>Then, for reasons I can't explain, it waits a long time
2386 (typically 2 minutes) after the ack is sent before sending the next
2387 (fragmented) packet. Turning off tcp timestamps avoids the
2388 fragmentation and restores normal behaviour. To do this,
2391 <p>echo 0 > /proc/sys/net/ipv4/tcp_timestamps</p>
2393 <p>I'm still unclear about the details of why this is happening. At
2394 least [now] I am now getting good performance and no queue
2399 <h2><a id="R9" name="R9">R9. Fetchmail is timing out during message
2402 <p>This is probably a general networking issue. Sending a "RETR"
2403 command will cause the server to start sending large amounts of
2404 data, which means large packets. If your networking layer has a
2405 packet-fragmentation problem, that's where you'll see it.</p>
2408 <h2><a id="R10" name="R10">R10. Fetchmail is dying with
2411 <p>This probably means you have an <code>mda</code> option. Your
2412 MDA is croaking while being passed a message. Best fix is to remove
2413 the <code>mda</code> option and pass mail to your port 25 SMTP
2416 <p>If for some reason you are invoking sendmail via the
2417 <tt>mda</tt> option (rather than delivering to port 25 via smtp),
2418 don't forget to include the -i switch. Otherwise you will
2419 occasionally get mysterious delivery failures with a SIGPIPE as the
2420 sendmail instance dies. The problem is messages with a single dot
2421 at start of a text line.</p>
2424 <h2><a id="R11" name="R11">R11. My server is hanging or emitting
2425 errors on CAPA.</a></h2>
2427 <p>Your POP3 server is broken. You can work around this with the
2428 declaration <tt>auth password</tt> in your .fetchmailrc.</p>
2431 <h2><a id="H1" name="H1">H1. Fetchmail hangs when used with
2434 <p>Your problem may be with pppd's `demand' option. We have a
2435 report that fetchmail doesn't play well with it, but works with
2436 pppd if `demand' is turned off. We have no idea why this is.</p>
2439 <h2><a id="H2" name="H2">H2. Fetchmail hangs during the MAIL FROM
2442 <p>The symptom: 'fetchmail -v' retrieves mail fine, but appears to
2443 hang after sending the MAIL FROM command</p>
2446 SMTP> MAIL FROM: <someone@somewhere>
2449 <p>The hang is actually occuring when sendmail looks up a sender's
2450 address in DNS. The problem isn't in fetchmail but in the
2451 configuration of sendmail. You must enable the 'nodns' and
2452 'nocanonify' features of sendmail.</p>
2454 <p>Here was my fix for RedHat 7.2:</p>
2457 <li># cd /etc/mail</li>
2459 <li># cp sendmail.mc sendmail-mine.mc</li>
2461 <li>Edit sendmail-mine.mc and add lines:
2469 <li>Build a new sendmail.cf
2472 # m4 sendmail-mine.cf > /etc/sendmail.cf
2476 <li>Restart sendmail.</li>
2479 <p>For more details consult the file
2480 /usr/share/sendmail-cf/README.</p>
2483 <h2><a id="H3" name="H3">H3. Fetchmail hangs while fetching
2486 <p>The symption: 'fetchmail -v' retrieves the first few messages,
2487 but hangs returning:</p>
2490 fetchmail: SMTP< 550 5.0.0 Access denied
2491 fetchmail: SMTP> RSET
2492 fetchmail: SMTP< 250 2.0.0 Reset state
2493 .......fetchmail: flushed
2494 fetchmail: POP3> DELE 1
2495 fetchmail: POP3< +OK marked deleted
2498 <p>Check and see if you're allowing sendmail connections through
2501 <p>Adding 'sendmail : 127.0.0.1' to /etc/hosts.allow could solve
2505 <h2><a id="D1" name="D1">D1. I think I've set up fetchmail
2506 correctly, but I'm not getting any mail.</a></h2>
2508 <p>Maybe you have a .forward or alias set up that you've forgotten
2509 about. You should probably remove it.</p>
2511 <p>Or maybe you're trying to run fetchmail in multidrop mode as
2512 root without a .fetchmailrc file. This doesn't do what you think it
2513 should; see question <a href="#C1">C1</a>.</p>
2515 <p>Or you may not be connecting to the SMTP listener. Run fetchmail
2516 -v and see <a href="#R1">R1</a>.</p>
2518 <p>Or you may have your local user set incorrectly. In the
2522 user 'remoteuser' there with password '*' is 'localuser' here
2525 <p>make sure that 'localuser' does exist and can receive mail.</p>
2528 <h2><a id="D2" name="D2">D2. All my mail seems to disappear after a
2529 dropped connection.</a></h2>
2531 <p>One POP3 daemon used in the Berkeley Unix world that reports
2532 itself as POP3 version 1.004 actually throws the queue away. 1.005
2533 fixed that. If you're running this one, upgrade immediately. (It
2534 also truncates long lines at column 1024)</p>
2536 <p>Many POP servers, if an interruption occurs, will restore the
2537 whole mail queue after about 10 minutes. Others will restore it
2538 right away. If you have an interruption and don't see it right
2539 away, cross your fingers and wait ten minutes before retrying.</p>
2541 <p>Some servers (such as Microsoft's NTMail) are mis-designed to
2542 restore the entire queue, including messages you have deleted. If
2543 you have one of these and it flakes out on you a lot, try setting a
2544 small <code>--fetchlimit</code> value. This will result in more IP
2545 connects to the server, but will mean it actually executes changes
2546 to the queue more often.</p>
2548 <p>Qualcomm's qpopper, used at many BSD Unix sites, is better
2549 behaved. If its connection is dropped, it will first execute all
2550 DELE commands as though you had issued a QUIT (this is a technical
2551 violation of the POP3 RFCs, but a good idea in a world of flaky
2552 phone lines). Then it will re-queue any message that was being
2553 downloaded at hangup time. Still, qpopper may require a noticeable
2554 amount of time to do deletions and clean up its queue. (Fetchmail
2555 waits a bit before retrying in order to avoid a `lock busy'
2559 <h2><a id="D3" name="D3">D3. Mail that was being fetched when I
2560 interrupted my fetchmail seems to have been vanished.</a></h2>
2562 <p>Fetchmail only sends a delete mail request to the server when
2563 either (a) it gets a positive delivery acknowledgment from the SMTP
2564 listener, or (b) it gets one of the spam-filter errors (see the
2565 description of the <code>antispam></code> option) from the
2566 listener. No interrupt can cause it to lose mail.</p>
2568 <p>However, IMAP2bis has a design problem in that its normal fetch
2569 command marks a message `seen' as soon as the fetch command to get
2570 it is sent down. If for some reason the message isn't actually
2571 delivered (you take a line hit during the download, or your port 25
2572 listener can't find enough free disk space, or you interrupt the
2573 delivery in mid-message) that `seen' message can lurk invisibly in
2574 your server mailbox forever.</p>
2576 <p>Workaround: add the `<code>fetchall</code>' keyword to your
2579 <p>Solution: switch to an <a href="http://www.imap.org">IMAP4</a>
2583 <h2><a id="M1" name="M1">M1. I've declared local names, but all my
2584 multidrop mail is going to root anyway.</a></h2>
2586 <p>Somehow your fetchmail is never recognizing the hostname part of
2587 recipient names it parses out of To/Cc/envelope-header lines as
2588 matching the name of the mailserver machine. To check this, run
2589 fetchmail in foreground with -v -v on. You will probably see a lot
2590 of messages with the format ``line rejected, %s is not an alias of
2591 the mailserver'' or ``no address matches; forwarding to %s.''</p>
2593 <p>These errors usually indicate some kind of DNS configuration
2594 problem either on the server or your client machine.</p>
2596 <p>The easiest workaround is to add a `<code>via</code>' option (if
2597 necessary) and add enough aka declarations to cover all of your
2598 mailserver's aliases, then say `<code>no dns</code>'. This will
2599 take DNS out of the picture (though it means mail may be
2600 uncollected if it's sent to an alias of the mailserver that you
2601 don't have listed).</p>
2603 <p>It would be better to fix your DNS, however. DNS problems can
2604 hurt you in lots of ways, for example by making your machines
2605 intermittently or permanently unreachable to the rest of the
2608 <p>Occasionally these errors indicate the sort of header-parsing
2609 problem described in <a href="#M7">M7</a>.</p>
2612 <h2><a id="M2" name="M2">M2. I can't seem to get fetchmail to route
2613 to a local domain properly.</a></h2>
2615 <p>A lot of people want to use fetchmail as a poor man's
2616 internetwork mail gateway, picking up mail accumulated for a whole
2617 domain in a single server mailbox and then routing based on what's
2618 in the To/Cc/Bcc lines.</p>
2620 <p>In general, this is not really a good idea. It would be smarter
2621 to just let the mail sit in the mailserver's queue and use
2622 fetchmail's ETRN or ODMR modes to trigger SMTP sends periodically
2623 (of course, this means you have to poll more frequently than the
2624 mailserver's expiration period). If you can't arrange this, try
2625 setting up a UUCP feed.</p>
2627 <p>If neither of these alternatives is available, multidrop mode
2628 may do (though you <em>are</em> going to get hurt by some mailing
2629 list software; see the caveats under THE USE AND ABUSE OF MULTIDROP
2630 MAILBOXES on the man page). If you want to try it, the way to do it
2631 is with the `<code>localdomains</code>' option.</p>
2633 <p>In general, if you use localdomains you need to make sure of two
2636 <p><strong>1. You've actually set up your .fetchmailrc entry to
2637 invoke multidrop mode.</strong></p>
2639 <p>Many people set a `<code>localdomains</code>' list and then
2640 forget that fetchmail wants to see more than one name (or the
2641 wildcard `*') in a `<code>here</code>' list before it will do
2642 multidrop routing.</p>
2644 <p><strong>2. You may have to set `no envelope'.</strong></p>
2646 <p>Normally, multidrop mode tries to deduce an envelope address
2647 from a message before parsing the To/Cc/Bcc lines (this enables it
2648 to avoid losing to mailing list software that doesn't put a
2649 recipient address in the To lines).</p>
2651 <p>Some ways of accumulating a whole domain's messages in a single
2652 server mailbox mean it all ends up with a single envelope address
2653 that is useless for rerouting purposes. You may have to set
2654 `<code>no envelope</code>' to prevent fetchmail from being
2655 bamboozled by this.</p>
2657 <p>Check also answer <a href="#T1">T1</a> on a reliable way to do
2658 multidrop delivery if your ISP (or your mail redirection provider)
2662 <h2><a id="M3" name="M3">M3. I tried to run a mailing list using
2663 multidrop, and I have a mail loop!</a></h2>
2665 <p>This isn't fetchmail's fault. Check your mailing list. If the
2666 list expansion includes yourself or anybody else at your mailserver
2667 (that is, not on the client side) you've created a mail loop. Just
2668 chop the host part off any local addresses in the list.</p>
2670 <p>If you use sendmail, you can check the list expansion with
2671 <code>sendmail -bv</code>.</p>
2674 <h2><a id="M4" name="M4">M4. My multidrop fetchmail seems to be
2675 having DNS problems.</a></h2>
2677 <p>We have one report from a Linux user (not the same one as in <a
2678 href="#R1">R1</a>!) who solved this problem by removing the
2679 reference to -lresolv from his link line and relinking. Apparently
2680 in some older Linux distributions the libc5 bind library version
2683 <p>As of 2.2, the configure script has been hacked so the bind
2684 library is linked only if it is actually needed. So under Linux it
2685 won't be, and this problem should go away.</p>
2688 <h2><a id="M5" name="M5">M5. I'm seeing long DNS delays before each
2689 message is processed.</a></h2>
2691 <p>Use the `<code>aka</code>' option to pre-declare as many of your
2692 mailserver's DNS names as you can. When an address's host part
2693 matches an aka name, no DNS lookup needs to be done to check
2696 <p>If you're sure you've pre-declared all of your mailserver's DNS
2697 names, you can use the `<code>no dns</code>' option to prevent
2698 other hostname parts from being looked up at all.</p>
2700 <p>Sometimes delays are unavoidable. Some SMTP listeners try to
2701 call DNS on the From-address hostname as a way of checking that the
2702 address is valid.</p>
2705 <h2><a id="M6" name="M6">M6. How do I get multidrop mode to work
2706 with majordomo?</a></h2>
2708 <p>In order for sendmail to execute the command strings in the
2709 majordomo alias file, it is necessary for sendmail to think that
2710 the mail it receives via SMTP really is destined for a local user
2711 name. A normal virtual-domain setup results in delivery to the
2712 default mailbox, rather than expansion through majordomo.</p>
2714 <p>Michael <michael@bizsystems.com> gave us a recipe for
2715 dealing with this case that pairs a run control file like this:</p>
2718 poll your.pop3.server proto pop3:
2720 localdomains virtual.localdomain1.com virtual.localdomain2.com ...
2721 user yourISPusername is root * here,
2722 password yourISPpassword fetchall
2725 <p>with a hack on your local sendmail.cf like this:</p>
2728 #############################################
2729 # virtual info, local hack for ruleset 98 #
2730 #############################################
2732 # domains to treat as direct mapped local domain
2734 CVvirtual.localdomain1.com virtual.localdomain2.com ...
2735 ---------------------------
2737 -------------------------
2738 # handle virtual users
2740 R$+ <@ $=V . > $: $1 < @ $j . >
2741 R< @ > $+ < @ $=V . > $: $1 < @ $j . >
2742 R< @ > $+ $: $1
2743 R< error : $- $+ > $* $#error $@ $1 $: $2
2744 R< $+ > $+ < @ $+ > $: $>97 $1
2747 <p>This ruleset just strips virtual domain names off the addresses
2748 of incoming mail. Your sendmail must be 8.8 or newer for this to
2749 work. Michael says:</p>
2751 <blockquote>I use this scheme with 2 virtual domains and the
2752 default ISP user+domain and service about 30 mail accounts +
2753 majordomo on my inside pop3 server with fetchmail and sendmail
2757 <h2><a id="M7" name="M7">M7. Multidrop mode isn't parsing envelope
2758 addresses from my Received headers as it should.</a></h2>
2760 <p>It may happen that you're getting what appear to be well-formed
2761 sendmail Received headers, but fetchmail can't seem to extract an
2762 envelope address from them. There can be a couple of reasons for
2765 <h3>Spurious Received lines need to be skipped:</h3>
2767 <p>First, fetchmail might be looking at the wrong Received header.
2768 Normally it looks only on the first one it sees, on the theory that
2769 that one was last added and is going to be the one containing your
2770 mailserver's theory of who the message was addressed to.</p>
2772 <p>Some (unusual) mailserver configurations will generate extra
2773 Received lines which you need to skip. To arrange this, use the
2774 optional skip prefix argument of the `envelope' option; you may
2775 need to say something like `<code>envelope 1 Received</code>' or
2776 `<code>envelope 2 Received</code>'.</p>
2778 <h3>The `by' clause doesn't contain a mailserver alias:</h3>
2780 <p>When fetchmail parses a Received line that looks like</p>
2783 Received: from send103.yahoomail.com (send103.yahoomail.com [205.180.60.92])
2784 by iserv.ttns.net (8.8.5/8.8.5) with SMTP id RAA10088
2785 for <ksturgeon@fbceg.org>; Wed, 9 Sep 1998 17:01:59 -0700
2788 <p>it checks to see if `iserv.ttns.net' is a DNS alias of your
2789 mailserver before accepting `ksturgeon@fbceg.org' as an envelope
2790 address. This check might fail if your DNS were misconfigured, or
2791 if you were using `no dns' and had failed to declare iserv.ttns.net
2792 as an alias of your server.</p>
2795 <h2><a id="M8" name="M8">M8. Users are getting multiple copies of
2798 <p>It's a consequence of multidrop. What's happening is that you
2799 have N users subscribed to the same list. The list software sends N
2800 copies, not knowing they will end up in the same multidrop box.
2801 Since they are both locally addressed to all N users, fetchmail
2802 delivers N copies to each user.</p>
2804 <p>Fetchmail tries to eliminate adjacent duplicate messages in a
2805 multidrop mailbox. However, this logic depends on the message-ID
2806 being identical in both copies. It also depends on the two copies
2807 being adjacent in the server mailbox. The former is usually the
2808 case, but the latter condition sometimes fails in a
2809 timing-dependent way if the server was processing multiple incoming
2812 <p>I could eliminate this problem by keeping a list of all
2813 message-IDs received during a poll so far and dropping any message
2814 that matches a seen mail ID. The trouble is that this is an O(N**2)
2815 operation that might significantly slow down the retrieval of large
2819 <h2><a id="X1" name="X1">X1. Spurious blank lines are appearing in
2820 the headers of fetched mail.</a></h2>
2822 <p>What's probably happening is that the POP/IMAP daemon on your
2823 mailserver is inserting a non-RFC822 header (like X-POP3-Rcpt:) and
2824 something in your delivery path (most likely an old version of the
2825 <em>deliver</em> program, which sendmail often calls to do local
2826 delivery) is failing to recognize it as a header.</p>
2828 <p>This is not fetchmail's problem. The first thing to try is
2829 installing a current version of <em>deliver</em>. If this doesn't
2830 work, try to figure out which other program in your mail path is
2831 inserting the blank line and replace that. If you can't do either
2832 of these things, pick a different MDA (such as procmail) and
2833 declare it with the `<code>mda</code>' option.</p>
2836 <h2><a id="X2" name="X2">X2. My mail client can't see a Subject
2839 <p>First, see <a href="#X1">X1</a>. This is quite probably the same
2840 problem (X-POP3-Rcpt header or something similar being inserted by
2841 the server and choked on by an old version of
2842 <em>deliver</em>).</p>
2844 <p>The O'Reilly sendmail book does warn that IDA sendmail doesn't
2845 process X- headers correctly. If this is your problem, all I can
2846 suggest is replacing IDA sendmail, because it's broken and not
2847 RFC822 conformant.</p>
2850 <h2><a id="X3" name="X3">X3. Messages containing "From" at start of
2851 line are being split.</a></h2>
2853 <p>If you know the messages aren't split in your server mailbox,
2854 then this is a problem with your POP/IMAP server, your client-side
2855 SMTP listener or your local delivery agent. Fetchmail cannot split
2858 <p>Some POP server daemons ignore Content-Length headers and split
2859 messages on From lines. We have one report that the 2.1 version of
2860 the BSD popper program (as distributed on Solaris 2.5 and
2861 elsewhere) is broken this way.</p>
2863 <p>You can test this. Declare an mda of `cat' and send yourself one
2864 piece of mail containing "From" at start of a line. If you see a
2865 split message, your POP/IMAP server is at fault. Upgrade to a more
2868 <p>Sendmail and other SMTP listeners don't split RFC822 messages
2869 either. What's probably happening is either sendmail's local
2870 delivery agent or your mail reader are not quite RFC822-conformant
2871 and are breaking messages on what it thinks are Unix-style From
2872 headers. You can figure out which by looking at your client-side
2873 mailbox with vi or more. If the message is already split in your
2874 mailbox, your local delivery agent is the problem. If it's not,
2875 your mailreader is the problem.</p>
2877 <p>If you can't replace the offending program, take a look at your
2878 sendmail.cf file. There will likely be a line something like</p>
2881 Mlocal, P=/usr/bin/procmail, F=lsDFMShP, S=10, R=20/40, A=procmail -Y -d $u
2884 <p>describing your local delivery agent. Try inserting the `E'
2885 option in the flags part (the F= string). This will make sendmail
2886 turn each dangerous start-of-line From into a >From, preventing
2887 programs further downstream from acting up.</p>
2890 <h2><a id="X4" name="X4">X4.</a><a id="generic_mangling"
2891 name="generic_mangling">My mail is being mangled in a new and
2892 different way</a></h2>
2894 <p>The first thing you need to do is pin down what program is doing
2895 the mangling. We don't like getting bug reports about fetchmail
2896 that are actually due to some other program's malfeasance, so
2897 please go through this diagnostic sequence before sending us a
2900 <p>There are five possible culprits to consider, listed here in the
2901 order they pass your mail:</p>
2904 <li>Programs upstream of your server mailbox.</li>
2906 <li>The POP or IMAP server on your mailserver host.</li>
2908 <li>The fetchmail program itself.</li>
2910 <li>Your local sendmail.</li>
2912 <li>Your LDA (local delivery agent), as called by sendmail or
2913 specified by <code>mda</code>.</li>
2916 <p>Often it happens that fetchmail itself is OK, but using it
2917 exposes pre-existing bugs in your downstream software, or your
2918 downstream software has a bad interaction with POP/IMAP. You need
2919 to pin down exactly where the message is being garbled in order to
2920 deduce what is actually going on.</p>
2922 <p>The first thing to do is send yourself a test message, and
2923 retrieve it with a .fetchmailrc entry containing the following (or
2924 by running with the equivalent command-line options):</p>
2927 mda "cat >MBOX" keep fetchall
2930 <p>This will capture what fetchmail gets from the server, except
2931 for (a) the extra Received header line fetchmail prepends, (b)
2932 header address changes due to <code>rewrite</code>, and (c) any
2933 end-of-line changes due to the <code>forcecr</code> and
2934 <code>stripcr</code> options. MBOX will in fact contain what
2935 programs downstream of fetchmail see.</p>
2937 <p>The most common causes of mangling are bugs and
2938 misconfigurations in those downstream programs. If MBOX looks
2939 unmangled, you will know that is what is going on and that it is
2940 not fetchmail's problem. Take a look at the other FAQ items in this
2941 section for possible clues about how to fix your problem.</p>
2943 <p>If MBOX looks mangled, the next thing to do is compare it with
2944 your actual server mailbox (if possible). That's why you specified
2945 <code>keep</code>, so the server copy would not be deleted. If your
2946 server mailbox looks mangled, programs upstream of your server
2947 mailbox are at fault. Unfortunately there is probably little you
2948 can do about this aside from complaining to your site postmaster,
2949 and nothing at all fetchmail can do about it!</p>
2951 <p>More likely you'll find that the server copy looks OK. In that
2952 case either the POP/IMAP server or fetchmail is doing the mangling.
2953 To determine which, you'll need to telnet to the server port and
2954 simulate a fetchmail session yourself. This is not actually hard
2955 (both POP3 and IMAP are simple, text-only, line-oriented protocols)
2956 but requires some attention to detail. You should be able to use a
2957 fetchmail -v log as a model for a session, but remember that the
2958 "*" in your LOGIN or PASS command dump has to be replaced with your
2959 actual password.</p>
2961 <p>The objective of manually simulating fetchmail is so you can see
2962 exactly what fetchmail sees. If you see a mangled message, then
2963 your server is at fault, and you probably need to complain to your
2964 mailserver administrators. However, we like to know what the broken
2965 servers are so we can warn people away from them. So please send us
2966 a transcript of the session including the mangling <em>and the
2967 server's initial greeting line</em>. Please tell us anything else
2968 you think might be useful about the server, like the server host's
2969 operating system.</p>
2971 <p>If your manual fetchmail simulation shows an unmangled message,
2972 congratulations. You've found an actual fetchmail bug, which is a
2973 pretty rare thing these days. Complain to us and we'll fix it.
2974 Please include the session transcript of your manual fetchmail
2975 simulation along with the other things described in the FAQ entry
2976 on <a href="#G3">reporting bugs</a>.</p>
2979 <h2><a id="X5" name="X5">X5. Using POP3, retrievals seems to be
2980 fetching too much!</a></h2>
2982 <p>This may happen in versions of fetchmail after 4.4.1 and before
2983 4.4.8. Versions after 4.4.1 use POP3's TOP command rather than
2984 RETR, in order to avoid marking the message seen (leaving it unseen
2985 is helpful for later recovery if you lose your connection in the
2986 middle of a retrieval).</p>
2988 <p>Versions of fetchmail from 4.4.2 through 4.4.7 had a bad
2989 interaction with Eudora qpopper versions 2.3 and later. The TOP
2990 bounds check was fooled by an overflow condition in the TOP
2991 argument. Decrementing the TOP argument in 4.4.7 fixed this.</p>
2993 <p>Fix: Upgrade to a later version of fetchmail.</p>
2995 <p>Workaround: set the <code>fetchall</code> option. Under POP3
2996 this has the side effect of forcing RETR use.</p>
2999 <h2><a id="X6" name="X6">X6. My mail attachments are being dropped
3000 or mangled.</a></h2>
3002 <p>Fetchmail doesn't discard attachments; fetchmail doesn't have any idea
3003 that attachments are there. Fetchmail treats the body of each message as
3004 an uninterpreted byte stream and passes it through without alteration.
3005 If you are not receiving attachments through fetchmail, it is because
3006 your mailserver is not sending them to you.</p>
3008 <p>The fix for this is to replace your mailserver with one that works.
3009 If its operating system makes this difficult, you should replace its
3010 operating system with one that works. Windows- and NT-based POP servers
3011 seem especially prone to mangle attachments. If you are running one
3012 of these, replacing your server with a Unix machine is probably the
3013 only effective solution.</p>
3015 <p>We've had sporadic reports of problems with Microsoft Exchange and
3016 Outlook servers. These sometimes randomly fail to ship
3017 attachments to your client. This is a known bug, acknowledged by
3020 <p>They may also mangle the attachments they do pass through. If you
3021 see unreadable attachments with a ContentType of "application/x-tnef",
3022 you're having this problem. The <a
3023 href="http://world.std.com/~damned/software.html">TNEF</a> utility may
3026 <p>The Mail Max POP3 server and the InterChange and Imail IMAP
3027 servers are known to simply drop MIME attachments when uploading
3030 <p>We've also had a report that Lotus Notes sometimes trashes the
3031 MIME type of messages. In particular, it seems to modify MIME
3032 headers of type application/pdf, mangling the type to
3033 application/octet-stream. It may corrupt other MIME types as
3036 <p>The IMAP service of Lotus Domino has a known bug in the way it
3037 generates MIME Content-type headers (observed on Lotus Domino
3038 5.0.2b). It's a subtle one that doesn't show up when Netscape
3039 Messenger and other clients use a FETCH BODY[] to grab the whole
3040 message. When fetchmail uses FETCH RFC822.HEADER and FETCH
3041 RFC822.TEXT to get first the header and then the body, Domino
3042 generates different Boundary tags for each part, .e.g. one tag is
3043 declared in the Content-type header and another is used to separate
3044 the MIME parts in the body. This doesn't work. (I have heard a
3045 rumor that this bug is scheduled to be fixed in Domino release 6;
3046 you can find a workaround at contrib/domino.)</p>
3048 <p>Rob Funk explains: Unfortunately there also remain many mail
3049 user agents that don't write correct MIME messages. One big
3050 offender is Sun MailTool attachments, which are formatted enough
3051 like MIME that some programs could get confused; these are
3052 generated by the mailtool and dtmail programs (the mail programs in
3053 Sun's OpenWindows and CDE environments).</p>
3055 <p>One solution to problems related to misformatted MIME
3056 attachments is the <a
3057 href="ftp://ftp.uu.se/pub/unix/networking/mail/emil/">emil</a>
3059 href="ftp://ftp.uu.se/pub/unix/networking/mail/emil/TUTORIAL.html">tutorial</a>
3060 file at that site for details on emil. It is useful for converting
3061 character sets, attachment encodings, and attachment formats. At
3062 this writing, emil does not appear to have been maintained since a
3063 patch to version 2.1.0beta9 in late 1997, but it is still
3066 <p>One good way of using emil is from within procmail. You can have
3067 procmail look for signs of problematic message formatting, and pipe
3068 those messages through emil to be fixed. emil will not always be
3069 able to fix the problem, in which case the message is
3072 <p>A possible rule to be inserted into a .procmailrc file for using
3077 * 1^1 ^Content-Type: \/X-sun[^;]*
3078 * 1^1 ^Content-Type: \/application/mac-binhex[^;]*
3079 * 1^1 ^Content-Transfer-Encoding: \/x-binhex[^;]*
3080 * 1^1 ^Content-Transfer-Encoding: \/x-uuencode[^;]*
3082 LOG="Converting $MATCH
3085 | emil -A B -T Q -B BA -C iso-8859-1 -H Q -F MIME \
3086 | gawk '{gsub(/\r\n?/,"\n");print $0}'
3090 <p>The "1^1" in the conditions is a way of specifying to procmail
3091 that if any one of the four listed expressions is found in the
3092 message, the total condition is considered true, and the message
3093 gets passed into emil. These four subconditions check whether the
3094 message has a Sun attachment, a binhex attachment, or a uuencoded
3095 attachment; there are others that could be added to check these
3096 things better and to check other relevant conditions. The "LOG="
3097 line writes a line into the procmail log; the lone double-quote
3098 beginning the following line makes sure the log entry gets an
3099 end-of-line character. The call to gawk (GNU awk) is for fixing
3100 end-of-line conventions, since emil sometimes leaves those in the
3101 format of the originating machine; it could probably be replaced
3102 with a sed subsitution.</p>
3104 <p>The emil call itself tries to ensure that the message uses:</p>
3107 <li>BinHex encoding for any Apple Macintosh-only attachments</li>
3109 <li>Quoted-Printable encoding for text (when necessary)</li>
3111 <li>Base64 Encoding for binary attachments</li>
3113 <li>iso-8859-1 character set for text (unfortunately emil can't yet
3114 convert from windows-1252 to iso-8859-1)</li>
3116 <li>Quoted-Printable encoding for headers</li>
3118 <li>MIME attachment format</li>
3121 <p>Most of these (the primary exceptions being the character set
3122 and the Apple binary format) are as they should be for good
3123 internet interoperability.</p>
3125 <p>Some mail servers (Lotus Domino is a suspect here) mangle
3126 Sun-formatted messages, so the conversion to MIME needs to happen
3127 before such programs see the message. The ideal is to rid the world
3128 of Sun-formatted messages: don't use mailtool for sending
3129 attachments (it doesn't understand MIME anyway, and most of the
3130 world doesn't understand its attachments, so it really shouldn't be
3131 used at all), and make sure dtmail is set to use MIME rather than
3132 mailtool's format.</p>
3135 <h2><a id="X7" name="X7">X7. Some mail attachments are hanging
3138 <p>This isn't fetchmail's problem either; fetchmail doesn't know
3139 anything about mail attachments and doesn't treat them any
3140 differently from plain message data.</p>
3142 <p>The most usual cause of this problem seems to be bugs in your
3143 network transport layer's capability to handle the very large
3144 TCP/IP packets that attachments tend to turn into. You can test
3145 this theory by trying to download the offending message through a
3146 webmail account; using HTTP for the message tends to simulate
3147 large-packet stress rather well, and you will probably find that
3148 the messages that seem to be choking fetchmail will make your HTTP
3149 download speed drop to zero.</p>
3151 <p>This problem can be caused by subtle bugs in the
3152 packet-reassembly layer of your TCP/IP stack; these often don't
3153 manifest at normal packet sizes. It may also be caused by
3154 malfunctioning path-MTU discovery on the mailserver. Or, if there's
3155 a modem in the link, it may be because the attachment contains the
3156 Hayes mode escape "+++".</p>
3159 <h2><a id="X8" name="X8">X8. A spurious ) is being appended to my
3162 <p>Blame it on that rancid pile of dung and offal called Microsoft
3163 Exchange. Due to the problem described in <a href="#S2">S2</a>, the
3164 IMAP support in fetchmail cannot follow the IMAP protocol 100%.
3165 Most of the time it doesn't matter, but if you combine it with an
3166 SMTP server that behaves unusually, you'll get a spurious ) at
3169 <p>One piece of software that can trigger this is the Interchange
3170 mail server, as used by, e.g., mailandnews.com. Here's what
3173 <p>1. Someone sends mail to your account. The last line of the
3174 message contains text. So at the SMTP level, the message ends with,
3175 e.g. "blahblah\r\n.\r\n"</p>
3177 <p>2. The SMTP handler sees the final "\r\n.\r\n" and recognizes
3178 the end of the message. However, instead of doing the normal thing,
3179 which is tossing out the ".\r\n" and leaving the first '\r\n' as
3180 part of the email body, Interchange throws out the whole
3181 "\r\n.\r\n", and leaves the email body without any line terminator
3182 at the end of it. RFC821 does not forbid this, though it probably
3185 <p>3. Fetchmail, or some other IMAP client, asks for the message.
3186 IMAP returns it, but it's enclosed inside parentheses, according to
3187 the protocol. The message size in bytes is also present. Because
3188 the message doesn't end with a line terminator, the IMAP client
3196 <p>where the ')' is from IMAP.</p>
3198 <p>4. Fetchmail only deals with complete lines, and can't trust the
3199 stated message size because Microsoft Exchange fscks it up.</p>
3201 <p>5. As a result, fetchmail takes the final 'blahblah)' and puts
3202 it at the end of the message it forwards on. If you have verbosity
3203 on, you'll get a message about actual != expected.</p>
3205 <p>There is no fix for this. The nuke mentioned in <a
3206 href="#S2">S2</a> looks more tempting all the time.</p>
3209 <h2><a id="O1" name="O1">O1. The --logfile option doesn't work if
3210 the logfile doesn't exist.</a></h2>
3212 <p>This is a feature, not a bug. It's in line with normal practice
3213 for system daemons and allows you to suppress logging by removing
3214 the log, without hacking potentially fragile startup scripts. To
3215 get around it, just touch(1) the logfile before you run fetchmail
3216 (this will have no effect on the contents of the logfile if it
3217 already exists).</p>
3220 <h2><a id="O2" name="O2">O2. Every time I get a POP or IMAP message
3221 the header is dumped to all my terminal sessions.</a></h2>
3223 <p>Fetchmail uses the local sendmail to perform final delivery,
3224 which Netscape and other clients doesn't do; the announcement of
3225 new messages is done by a daemon that sendmail pokes. There should
3226 be a ``biff'' command to control this. Type</p>
3232 <p>to turn it off. If this doesn't work, try the command</p>
3238 <p>which is essentially what <code>biff -n</code> will do. If this
3239 doesn't work, comment out any reference to ``comsat'' in your
3240 /etc/inetd.conf file and restart inetd.</p>
3242 <p>In Slackware Linux distributions, the last line in /etc/profile
3255 to solve the problem system-wide.
3258 <h2><a id="O3" name="O3">O3. Does fetchmail reread its rc file
3259 every poll cycle?</a></h2>
3261 <p>No, but versions 5.2.2 and later will notice when you modify
3262 your rc file and restart, reading it.</p>
3265 <h2><a id="O4" name="O4">O4. Why do deleted messages show up again
3266 when I take a line hit while downloading?</a></h2>
3268 <p>Because you're using a POP3 other than Qualcomm qpopper, or an
3269 IMAP with a long expunge interval.</p>
3271 <p>According to the POP3 RFCs, deletes aren't actually performed
3272 until you issue the end-of-session QUIT command. Fetchmail cannot
3273 fix this, because doing it right takes cooperation from the server.
3274 There are two possible remedies:</p>
3276 <p>One is to switch to qpopper (the free POP3 server from Qualcomm,
3277 the Eudora people). The qpopper software violates the POP3 RFCs by
3278 doing an expunge (removing deleted messages) on a line hangup, as
3279 well as on processing a QUIT command.</p>
3281 <p>The other (which we recommend) is to switch to <a
3282 href="http://www.imap.org">IMAP</a>. IMAP has an explicit expunge
3283 command and fetchmail normally uses it to delete messages
3284 immediately after they are downloaded.</p>
3286 <p>If you get very unlucky, you might take a line hit in the window
3287 between the delete and the expunge. If you've set a longer expunge
3288 interval, the window gets wider. This problem should correct itself
3289 the next time you complete a successful query.</p>
3292 <h2><a id="O5" name="O5">O5. Why is fetched mail being logged with
3293 my name, not the real From address?</a></h2>
3295 <p>Because logging is done based on the address indicated by the
3296 sending SMTP's MAIL FROM, and some listeners are picky about that
3299 <p>Some SMTP listeners get upset if you try to hand them a MAIL
3300 FROM address naming a different host than the originating site for
3301 your connection. This is a feature, not a bug -- it's supposed to
3302 help prevent people from forging mail with a bogus origin site.
3303 (RFC 1123 says you shouldn't do this exclusion...)</p>
3305 <p>Since the originating site of a fetchmail delivery connection is
3306 localhost, this effectively means these picky listeners will barf
3307 on any MAIL FROM address fetchmail hands them with an @ in it!</p>
3309 <p>Versions 2.1 and up try the header From address first and fall
3310 back to the calling-user ID. So if your SMTP listener isn't picky,
3311 the log will look right.</p>
3314 <h2><a id="O6" name="O6">O6. I'm seeing long sendmail delays or
3315 hangs near the start of each poll cycle.</a></h2>
3317 <p>Sendmail does a hostname lookup when it first starts up, and
3318 also each time it gets a HELO in listener mode.</p>
3320 <p>Your resolver configuration may be causing one of these lookups
3321 to fail and time out. Check <code>/etc/resolv.conf</code> and
3322 <code>/etc/hosts</code> file. Make sure your hostname and
3323 fully-qualified domain name are both in <code>/etc/hosts</code>,
3324 and that hosts is looked at before DNS is queried. You probably
3325 also want your remote mail server(s) to be in the hosts file.</p>
3327 <p>You can suppress the startup-time lookup if need to by
3328 reconfiguring with <code>FEATURE(nodns)</code>.</p>
3330 <p>Configuring your bind library to cache DNS lookups locally may
3331 help, and is a good idea for speeding up other services as well.
3332 Switching to a faster MTA like qmail or exim might help.</p>
3335 <h2><a id="O7" name="O7">O7. Why doesn't fetchmail deliver mail in
3336 date-sorted order?</a></h2>
3338 <p>Because that's not the order the server hands it to fetchmail
3341 <p>Fetchmail getting mail from a POP server delivers mail in the
3342 order that your server delivers mail. Fetchmail can't do anything
3343 about this; it's a limitation of the underlying POP protocol.</p>
3345 <p>In theory it might be possible for fetchmail in IMAP mode to
3346 sort messages by date, but this would be in violation of two basics
3347 of fetchmail's design philosophy: (a) to be as simple and
3348 transparent a pipe as possible, and (b) to <em>hide</em>, rather
3349 than emphasize, the differences between the remote-fetch protocols
3352 <p>Re-ordering messages is a user-agent function, anyway.</p>
3355 <h2><a id="O8" name="O8">O8. I'm using pppd. Why isn't my monitor
3356 option working?</a></h2>
3358 <p>There is a combination of circumstances that can confuse
3359 fetchmail. If you have set up demand dialing with pppd, and pppd
3360 has an idle timeout, and you have lcp-echo-interval set, then the
3361 lcp-echo-interval time must be longer than the pppd idle timeout.
3362 Otherwise it is going keep increasing the packet counters that
3363 fetchmail relies upon, triggering fetchmail into polling after its
3364 own delay interval and thus preventing the pppd link from ever
3365 reaching its inactivity timeout.</p>
3368 <h2><a id="O9" name="O9">O9. Why does fetchmail keep retrieving the
3369 same messages over and over?</a></h2>
3371 <p>First, check to see that you haven't enabled the
3372 <cite>keep</cite> and <cite>fetchall</cite> option. If you have,
3373 turn <cite>keep</cite> off.</p>
3375 <p>There are various forms of lossage involving the POP3 UIDL
3376 feature that can lead to all your old messages being seen again
3377 after a line drop. I have given up trying to fix these, as the UIDL
3378 code breaks worse every time I touch it. The problem is
3379 fundamental; maintaining and garbage-collecting the right kind of
3380 client-side state is just hard. Whoever put UIDLs in RFC1725 and
3381 removed LAST should be hung up by his thumbs and whipped with
3382 scorpions. The right answers are either (a) live with the
3383 occasional breakage, (b) switch to IMAP4, or (c) fix the code
3384 yourself and send me a patch. Unless you choose (c), I don't want
3385 to hear about it.</p>
3387 <p>This can also happen when some other mail client is logged in to
3388 your mail server, if it uses a simple exclusive-locking scheme (and
3389 many, especially most POP3 servers, do exactly that). Your
3390 fetchmail is able to retrieve the messages, but because the mailbox
3391 is write-locked by the other instance yours can neither mark
3392 messages seen or delete them. The solution is to either (a) wait
3393 for the other client to finish, or (b) terminate it.</p>
3395 <p>James Stevens <James.Stevens@kyzo.com> writes:</p>
3397 <p><em>We had a Linux box dialing the Net and collecting mail from
3398 an NT POP3 server. Fetchmail was correctly collecting and deleting
3399 each e-mail one by one. However,the dial-up connection was very
3400 unreliable and would often just drop out in the middle of a
3403 <p><em>Interestingly, unless the TCP POP3 connection was terminated
3404 normally (I guess with a POP3 "QUIT" command) NT would then roll
3405 back all the deletes !!!</em></p>
3407 <p><em>This meant if the first e-mail was very large it might just
3408 end up continuously collecting it, basically jamming the queue. Or,
3409 if the queue became very full itmight never get a long enough phone
3410 connection to retrieve the entire mailbox, and NT would roll back
3411 any deletes, so it would end up collecting (and delivering) the
3412 first few e-mails again and again. As the POP3 mailbox became
3413 fuller and fuller the chances of getting a connection long enough
3414 to collect theentire mailbox became smaller and smaller.</em></p>
3416 <p><em>Our solution was to make fetchmail only collect a few (say 5
3417 or 10) e-mails at atime, thus trying to ensure that the POP3
3418 connection is terminated correctly.</em></p>
3420 <p>Unfortunately, this is exactly the way POP3 servers are supposed
3421 to behave on a line drop, according to the RFCs. I recommend
3422 switching to IMAP and using a short expunge interval.</p>
3425 <h2><a id="O10" name="O10">O10. Why is the received date on all my
3426 messages the same?</a></h2>
3428 <p>This is a design choice in your MTA, not fetchmail. It's taking
3429 the received date from the last Received header.</p>
3432 <h2><a name="#O11">O11. I keep getting messages that say "Repoll
3433 immediately" in my logs.</a></h2>
3435 <p>This is your server barfing on the CAPA probe that fetchmail sends.</p>
3436 If you run fetchmail in daemon mode (say "set daemon 600"), you will
3437 get the message only once per run.</p>
3439 <p>If you set an authentication method explicitly (say, with
3440 <code>auth password</code>), you will never get the message.</p>
3443 <h2><a name="#O12">O12. Fetchmail no longer expunges mail on a 451 SMTP response.</a></h2>
3445 <p>This is a feature, not a bug.</p>
3447 <p>Any 4xx response (like 451) indicates a transient (temporary) error.
3448 This means that the mail could be accepted if retried later. Lookup
3449 failures are normally transient errors as a mail should not get
3450 rejected if a dns server is unreachable or down.</p>
3452 <p>A permanent reject response is of the form 5xx (like 550).</p>
3454 <p>You could tell your SMTP server to not lookup any addresses if you are
3455 not keen on checking the sender addresses. This problem typically
3456 occurs if your mail server is not checking the sender addresses, but
3457 your local server is.</p>
3459 <p>Or you could declare <code>antispam 451<code></p>
3461 <p>Or, you could check your nameserver configuration and query logs for
3464 <p>All these issues are not related to fetchmail directly.</p>
3467 <h2><a name="#O13">O13. I want timestamp information in my fetchmail logs.</a></h2>
3469 <p>Write a <code>preconnect</connect> command in your configuration file that
3470 does something like "date >> $HOME/Procmail/fetchmail.log".</p>
3473 <table width="100%" cellpadding="0" summary="Canned page footer">
3475 <td width="30%">Back to <a href="index.html">Fetchmail Home
3477 <td width="30%" align="center">To <a href="/~esr/sitemap.html">Site
3479 <td width="30%" align="right">$Date: 2003/08/06 04:31:10 $</td>
3484 <address>Eric S. Raymond <a
3485 href="mailto:esr@thyrsus.com"><esr@thyrsus.com></a></address>
3489 compile-command: "(cd ~/WWW; upload fetchmail/fetchmail-FAQ.html)"