1 <!doctype HTML public "-//W3O//DTD W3 HTML 3.2//EN">
4 <TITLE>The Fetchmail FAQ</TITLE>
5 <link rev=made href="mailto:esr@snark.thyrsus.com">
6 <meta name="description" content="Frequently asked questions about fetchmail.">
7 <meta name="keywords" content="fetchmail, POP, POP2, POP3, IMAP, remote mail">
10 <table width="100%" cellpadding=0><tr>
11 <td width="30%">Back to <a href="index.html">Fetchmail Home Page</a>
12 <td width="30%" align=center>To <a href="/~esr/sitemap.html">Site Map</a>
13 <td width="30%" align=right>$Date: 2000/11/11 18:20:46 $
16 <H1>Frequently Asked Questions About Fetchmail</H1>
18 Before reporting any bug, please read <a href="#G3">G3</a> for advice
19 on how to include diagnostic information that will get your bug fixed
20 as quickly as possible. <p>
22 If you have a question or answer you think ought to be added to this FAQ list,
23 mail it to fetchmail's maintainer, Eric S. Raymond, at
24 <A HREF="mailto:esr@thyrsus.com">esr@snark.thyrsus.com</A>.<p>
26 <h1>General questions:</h1>
28 <a href="#G1">G1. What is fetchmail and why should I bother?</a><br>
29 <a href="#G2">G2. Where do I find the latest FAQ and fetchmail sources?</a><br>
30 <a href="#G3">G3. I think I've found a bug. Will you fix it?</a><br>
31 <a href="#G4">G4. I have this idea for a neat feature. Will you add it?</a><br>
32 <a href="#G5">G5. Is there a mailing list for exchanging tips?</a><br>
33 <a href="#G6">G6. So, what's this I hear about a fetchmail paper?</a><br>
34 <a href="#G7">G7. What is the best server to use with fetchmail?</a><br>
35 <a href="#G8">G8. What is the best mail program to use with fetchmail?</a><br>
36 <a href="#G9">G9. How can I avoid sending my password en clair?</a><br>
37 <a href="#G10">G10. Is any special configuration needed to use a dynamic
39 <a href="#G11">G11. Is any special configuration needed to use firewalls?</a><br>
40 <a href="#G12">G12. Is any special configuration needed to <em>send</em> mail?</a><br>
41 <a href="#G13">G13. Is fetchmail Y2K-compliant?</a><br>
42 <a href="#G14">G14. Is there a way in fetchmail to support disconnected IMAP mode?</a><br>
43 <a href="#G15">G15. How will fetchmail perform under heavy loads?</a><br>
45 <h1>Build-time problems:</h1>
47 <a href="#B1">B1. Lex bombs out while building the fetchmail lexer.</a><br>
48 <a href="#B2">B2. I get link failures when I try to build fetchmail.</a><br>
50 <h1>Fetchmail configuration file grammar questions:</h1>
52 <a href="#F1">F1. Why does my old .fetchmailrc no longer work?</a><br>
53 <a href="#F2">F2. The .fetchmailrc parser won't accept my all-numeric user name.</a><br>
54 <a href="#F3">F3. The .fetchmailrc parser won't accept my host or username beginning with `no'.</a><br>
55 <a href="#F4">F4. I'm getting a `parse error' message I don't understand.</a><br>
57 <h1>Configuration questions:</h1>
59 <a href="#C1">C1. Why do I need a .fetchmailrc when running as root on my own machine?</a><br>
60 <a href="#C2">C2. How can I arrange for a fetchmail daemon to get killed when I log out?</a><br>
61 <a href="#C3">C3. How do I know what interface and address to use with --interface?</a><br>
62 <a href="#C4">C4. How can I set up support for sendmail's anti-spam features?</a><br>
63 <a href="#C5">C5. How can I poll some of my mailboxes more/less often than others?</a><br>
64 <a href="#C6">C6. Fetchmail works OK started up manually, but not from an init script.</a><br>
65 <a href="#C7">C7. How can I forward mail to another host?.</a><br>
67 <h1>How to make fetchmail play nice with various MTAs:</h1>
69 <a href="#T1">T1. How can I use fetchmail with sendmail?</a><br>
70 <a href="#T2">T2. How can I use fetchmail with qmail?</a><br>
71 <a href="#T3">T3. How can I use fetchmail with exim?</a><br>
72 <a href="#T4">T4. How can I use fetchmail with smail?</a><br>
73 <a href="#T5">T5. How can I use fetchmail with SCO's MMDF?</a><br>
74 <a href="#T6">T6. How can I use fetchmail with Lotus Notes?</a><br>
76 <h1>How to make fetchmail work with various servers:</h1>
78 <a href="#S1">S1. How can I use fetchmail with qpopper?</a><br>
79 <a href="#S2">S2. How can I use fetchmail with Microsoft Exchange?</a><br>
80 <a href="#S3">S3. How can I use fetchmail with Compuserve RPA?</a><br>
81 <a href="#S4">S4. How can I use fetchmail with Demon Internet's SDPS?</a><br>
82 <a href="#S5">S5. How can I use fetchmail with usa.net's servers?</a><br>
83 <a href="#S6">S6. How can I use fetchmail with HP OpenMail?</a><br>
84 <a href="#S7">S7. How can I use fetchmail with geocities POP3 servers?</a><br>
85 <a href="#S8">S8. How can I use fetchmail with Hotmail?</a><br>
86 <a href="#S9">S9. How can I use fetchmail with MSN?</a><br>
87 <a href="#S10">S10. How can I use fetchmail with SpryNet?</a><br>
88 <a href="#S11">S11. How can I use fetchmail with FTGate?</a><br>
89 <a href="#S12">S12. How can I use fetchmail with MailMax?</a><br>
90 <a href="#S13">S13. How can I use fetchmail with Novell GroupWise?</a><br>
91 <a href="#S14">S14. How can I use fetchmail with InterChange?</a><br>
93 <h1>How to set up well-known security and authentication methods:</h1>
95 <a href="#K1">K1. How can I use fetchmail with SOCKS?</a><br>
96 <a href="#K2">K2. How can I use fetchmail with IPv6 and IPsec?</a><br>
97 <a href="#K3">K3. How can I get fetchmail to work with ssh?</a><br>
98 <a href="#K4">K4. What do I have to do to use the IMAP-GSS protocol?</a><br>
99 <a href="#K5">K5. How can I use fetchmail with SSL?</a><br>
101 <h1>Runtime fatal errors:</h1>
103 <a href="#R1">R1. Fetchmail isn't working, and -v shows `SMTP connect failed' messages.</a><br>
104 <a href="#R2">R2. When I try to configure an MDA, fetchmail doesn't work.</a><br>
105 <a href="#R3">R3. Fetchmail dumps core when given an invalid rc file.</a><br>
106 <a href="#R4">R4. Fetchmail dumps core in -V mode, but operates normally otherwise.</a><br>
107 <a href="#R5">R5. Running fetchmail in daemon mode doesn't work.</a><br>
108 <a href="#R6">R6. Fetchmail hangs when used with pppd.</a><br>
109 <a href="#R7">R7. Fetchmail randomly dies with socket errors.</a><br>
110 <a href="#R8">R8. Fetchmail running as root stopped working after an OS upgrade</a><br>
111 <a href="#R9">R9. Fetchmail is timing out after fetching certain
112 messages but before deleting them</a><br>
113 <a href="#R10">R10. Fetchmail is timing out during message fetches</a><br>
115 <h1>Disappearing mail</h1>
117 <a href="#D1">D1. I think I've set up fetchmail correctly, but I'm not getting any mail.</a><br>
118 <a href="#D2">D2. All my mail seems to disappear after a dropped connection.</a><br>
119 <a href="#D3">D3. Mail that was being fetched when I interrupted my fetchmail seems to have been vanished.</a><br>
121 <h1>Multidrop-mode problems:</h1>
123 <a href="#M1">M1. I've declared local names, but all my multidrop mail is going to root anyway.</a><br>
124 <a href="#M2">M2. I can't seem to get fetchmail to route to a local domain properly.</a><br>
125 <a href="#M3">M3. I tried to run a mailing list using multidrop, and I have a mail loop!</a><br>
126 <a href="#M4">M4. My multidrop fetchmail seems to be having DNS problems.</a><br>
127 <a href="#M5">M5. I'm seeing long DNS delays before each message is processed.</a><br>
128 <a href="#M6">M6. How do I get multidrop mode to work with majordomo?</a><br>
129 <a href="#M7">M7. Multidrop mode isn't parsing envelope addresses from
130 my Received headers as it should.</a><br>
131 <a href="#M8">M8. Users are getting multiple copies of messages.</a><br>
133 <h1>Mangled mail:</h1>
135 <a href="#X1">X1. Spurious blank lines are appearing in the headers of fetched mail.</a><br>
136 <a href="#X2">X2. My mail client can't see a Subject line.</a><br>
137 <a href="#X3">X3. Messages containing "From" at start of line are being split.</a><br>
138 <a href="#X4">X4. My mail is being mangled in a new and different way.</a><br>
139 <a href="#X5">X5. Using POP3, retrievals seems to be fetching too much!</a><br>
140 <a href="#X6">X6. My mail attachments are being dropped or mangled.</a><br>
141 <a href="#X7">X7. Some mail attachments are hanging fetchmail.</a><br>
143 <h1>Other problems:</h1>
145 <a href="#O1">O1. The --logfile option doesn't work if the logfile doesn't exist.</a><br>
146 <a href="#O2">O2. Every time I get a POP or IMAP message the header is
147 dumped to all my terminal sessions.</a><br>
148 <a href="#O3">O3. Does fetchmail reread its rc file every poll cycle?</a><br>
149 <a href="#O4">O4. Why do deleted messages show up again when I take
150 a line hit while downloading?</a><br>
151 <a href="#O5">O5. Why is fetched mail being logged with my name, not the real From address?</a><br>
152 <a href="#O6">O6. I'm seeing long sendmail delays or hangs near the start of each poll cycle.</a><br>
153 <a href="#O7">O7. Why doesn't fetchmail deliver mail in date-sorted order?</a><br>
154 <a href="#O8">O8. I'm using pppd. Why isn't my monitor option working?</a><br>
155 <a href="#O9">O9. Why does fetchmail keep retrieving the same messages
156 over and over?</a><br>
160 <h2><a name="G1">G1. What is fetchmail and why should I bother?</a></h2>
162 Fetchmail is a one-stop solution to the remote mail retrieval problem
163 for Unix machines, quite useful to anyone with an intermittent PPP or
164 SLIP connection to a remote mailserver. It can collect mail using any
165 variant of POP or IMAP and forwards via port 25 to the local SMTP
166 listener, enabling all the normal forwarding/filtering/aliasing
167 mechanisms that would apply to local mail or mail arriving via a
168 full-time TCP/IP connection.<p>
170 Fetchmail is not a toy or a coder's learning exercise, but an
171 industrial-strength tool capable of transparently handling every
172 retrieval demand from those of a simple single-user ISP connection up
173 to mail retrieval and rerouting for an entire client domain.
174 Fetchmail is easy to configure, unobtrusive in operation, powerful,
175 feature-rich, and well documented. <P>
177 Fetchmail is <a href="http://www.opensource.org">Open Source</a>
178 software. The openness of the sources is the strongest assurance of
179 quality you can have. Extensive peer review by a large,
180 multi-platform user community has shown that fetchmail is as near
181 bulletproof as the underlying protocols permit.<p>
183 Fetchmail is licensed under the <a
184 href="http://gnu.org//copyleft/gpl.html">GNU General Public
187 If you found this FAQ in the distribution, see the README for fetchmail's
188 full feature list.<p>
191 <h2><a name="G2">G2. Where do I find the latest FAQ and fetchmail
194 The latest HTML FAQ is available alongside the latest fetchmail
195 sources at the fetchmail home page:
196 <a href="http://www.tuxedo.org/~esr/fetchmail">
197 http://www.tuxedo.org/~esr/fetchmail</a>. You can also usually find
199 href="http://sunsite.unc.edu/pub/Linux/system/mail/pop/!INDEX.html">POP
200 mail tools directory on Sunsite</a>.<p>
202 A text dump of this FAQ is included in the fetchmail
203 distribution. Because it freezes at distribution release time, it may
204 not be completely current.<p>
207 <h2><a name="G3">G3. I think I've found a bug. Will you fix it?</a></h2>
209 Yes I will, provided you include enough diagnostic information for me
210 to go on. Send bugs to <a
211 href="mailto:fetchmail-friends@ccil.org">fetchmail-friends</a>. When reporting
212 bugs, please include the following:
215 <li>Your operating system.
216 <li>Your compiler version, if you built from source; otherwise, the
217 name and origin ogf the RPM or other binary package you installed.
218 <li>A copy of your POP or IMAP server's greeting line.
219 <li>The name and version of the SMTP listener or MDA you are forwarding to.
220 <li>Any command-line options you used.
221 <li>The output of fetchmail -V called with whatever other
222 command-line options you used.
225 If you have FTP access to your remote mail account, and you have any
226 suspicion that the bug was triggered by a particular message, please
227 include a copy of the message that triggered the bug.<p>
229 Often, the first thing I will do when you report a bug is tell you to
230 upgrade to the newest version of fetchmail, and then see if the
231 problem reproduces. So you'll probably save us both time if you
232 upgrade and test with the latest version <em>before</em> sending in a
235 Another useful thing you can do, if you're using POP3, is to test for
236 IMAP4 support on your mailserver using the autoprobe function of
237 fetchmailconf. If you have IMAP4, and fetchmailconf doesn't tell you
238 it's broken, switch immediately. POP3 is a weak, poorly-designed
239 protocol with chronic problems, and the later versions after RFC1725
240 actually get worse rather than better. Changing over to IMAP4 may well
241 make your problem go away -- and if your ISP doesn't have IMAP4
242 support, bug them to supply it.<p>
244 It is helpful if you include your .fetchmailrc file, but not necessary
245 unless your symptom seems to involve an error in configuration
246 parsing. If you do send in your .fetchmailrc, mask the passwords
249 If fetchmail seems to run and fetch mail, but the headers look mangled
250 (that is, headers are missing or blank lines are inserted in the
251 headers) then read the FAQ items in section <a href="#X1">X</a>
252 before submitting a bug report. Pay special attention to the item on
253 <a href="#generic_mangling">diagnosing mail mangling</a>. There are
254 lots of ways for other programs in the mail chain to screw up that
255 look like fetchmail's fault, but you may be able to fix these by
256 tweaking your configuration.<P>
258 A transcript of the failed session with -v -v (yes, that's
259 <em>two</em> -v options, enabling debug mode) will almost always be useful.
260 It is very important that the transcript include your POP/IMAP server's
261 greeting line, so I can identify it in case of server problems. This
262 transcript will not reveal your passwords, which are specially masked
263 out precisely so the transcript can be passed around.<P>
265 If the bug involves a core dump or hang, a gdb stack trace is good to have.
266 (Bear in mind that you can attach gdb to a running but hung process by
267 giving the process ID as a second argument.) You will need to
271 CFLAGS=-g LDFLAGS=" " ./configure
274 and then rebuild in order to generate a version that can be gdb-traced.<p>
276 Best of all is a mail file which, when fetched, will reproduce the
277 bug under the latest (current) version.<p>
279 Any bug I can reproduce will usually get fixed very quickly, often
280 within 48 hours. Bugs I can't reproduce are a crapshoot. If the
281 solution isn't obvious when I first look, it may evade me for a long
282 time (or to put it another way, fetchmail is well enough tested that the
283 easy bugs have long since been found). So if you want your bug fixed
284 rapidly, it is not just sufficient but nearly <em>necessary</em> that
285 you give me a way to reproduce it.<p>
288 <h2><a name="G4">G4. I have this idea for a neat feature. Will you add it?</a></h2>
290 Probably not. Most of the feature suggestions I get are for ways to
291 set various kinds of administrative policy or add more spam filtering
292 (the most common one, which I used to get about four million times a week
293 and got <em>really</em> tired of, is for tin-like kill files).<p>
295 You can do spam filtering better with procmail or maildrop on the
296 server side and (if you're the server sysadmin) sendmail.cf domain
297 exclusions. You can do other policy things better with the
298 <CODE>mda</CODE> option and script wrappers around fetchmail. If
299 it's a prime-time-vs.-non-prime-time issue, ask yourself whether a
300 wrapper script called from crontab would do the job.<p>
302 I'm not going to do these; fetchmail's job is transport, not policy, and I
303 refuse to change it from doing one thing well to attempting many things badly.
304 One of my objectives is to keep fetchmail simple so it stays reliable.<p>
306 For reasons fetchmail doesn't have other commonly-requested features
307 (such as password encryption, or multiple concurrent polls from the
308 same instance of fetchmail) see the <a
309 href="http://www.tuxedo.org/~esr/fetchmail/design-notes.html">design notes</a>.<p>
311 Fetchmail is a mature project, no longer in constant active
312 development. It is no longer my top project, and I am going to be
313 quite reluctant to add features that might either jeopardize its
314 stability or involve me in large amounts of coding.<p>
316 All that said, if you have a feature idea that really is about a transport
317 problem that can't be handled anywhere but fetchmail, lay it on me. I'm
318 very accommodating about good ideas.<p>
321 <h2><a name="G5">G5. Is there a mailing list for exchanging tips?</a></h2>
323 There is a fetchmail-friends list for people who want to discuss fixes
324 and improvements in fetchmail and help co-develop it. It's at <a
325 href="mailto:fetchmail-friends@thyrsus.com">fetchmail-friends@thyrsus.com</a>.
326 There is also an announcements-only list, <em>fetchmail-announce@thyrsus.com</em>.<P>
328 Both lists are SmartList reflectors; sign up in the usual way with a
329 message containing the word "subscribe" in the subject line sent to
330 <a href="mailto:fetchmail-friends-request@thyrsus.com?subject=subscribe">
331 fetchmail-friends-request@thyrsus.com</a> or
332 <a href="mailto:fetchmail-announce-request@thyrsus.com?subject=subscribe">
333 fetchmail-announce-request@thyrsus.com</a>. (Similarly, "unsubscribe"
334 in the Subject line unsubscribes you, and "help" returns general list help) <p>
337 <h2><a name="G6">G6. So, what's this I hear about a fetchmail paper?</a></h2>
339 The fetchmail development was also a sociological experiment, an
340 extended test to see if my theory about the critical features of the
341 Linux development model is correct.<p>
343 The experiment was a success. I wrote a paper about it titled <a
344 href="http://www.tuxedo.org/~esr/writings/cathedral.html">The
345 Cathedral and the Bazaar</a> which was first presented at Linux
346 Kongress '97 in Bavaria and very well received there. It was also
347 given at Atlanta Linux Expo, Linux Pro '97 in Warsaw, and the first
348 Perl Conference, at UniForum '98, and was the basis of an invited
349 presentation at Usenix '98. The folks at Netscape tell me it helped
351 href="http://www.netscape.com/newsref/pr/newsrelease558.html"> give
352 away the source for Netscape Communicator</a>.<p>
354 If you're reading a non-HTML dump of this FAQ, you can find the paper
355 on the Web with a search for that title.<p>
358 <h2><a name="G7">G7. What is the best server to use with fetchmail?</a></h2>
360 The short answer: IMAP4rev1 running over Unix.<P>
362 Here's a longer answer: <P>
364 Fetchmail will work with any POP, IMAP, or ESMTP/ETRN server that
365 conforms to the relevant RFCs (and even some outright broken ones like
366 <a href="#S2">Microsoft Exchange</a> and <a href="#S12">Novell
367 GroupWise</a>). This doesn't mean it works equally well with all,
368 however. POP2 servers, and POP3 servers without LAST, limit
369 fetchmail's capabilities in various ways described on the manual
372 Most modern Unixes (and effectively all Linux/*BSD systems) come with
373 POP3 support preconfigured (but beware of the horribly broken POP3
374 server mentioned in <a href="#D2">D2</a>). An increasing minority
375 also feature IMAP (you can detect IMAP support by running fetchmail in
376 AUTO mode, or by using the `Probe for supported protocols' function in
377 the fetchmailconf utility).<P>
379 If you have the option, we recommend using or installing an IMAP4rev1
380 server; it has the best facilities for tracking message `seen' states.
381 It also recovers from interrupted connections more gracefully than
382 POP3, and enables some significant performance optimizations.<P>
384 Don't be fooled by NT/Exchange propaganda. M$ Exchange is just plain
385 broken (see item <a href="#S2">S2</a>) and NT cannot handle the
386 sustained load of a high-volume remote mail server. Even Microsoft
387 itself knows better than to try this; their own Hotmail service runs
388 over Solaris! For extended discussion, see John Kirch's excellent <a
389 href="http://unix-vs-nt.org/kirch/">white paper</a> on Unix
390 vs. NT performance.<P>
392 You can find sources for IMAP software at <a
393 href="http://www.imap.org">The IMAP Connection</a>; we like the
394 open-source <a href="ftp://ftp.cac.washington.edu/imap/">UW IMAP</a>
395 server, which is the reference implementation of IMAP. UW IMAP's
396 support for GSSAPI gives you a good way to authenticate without
397 sending a password en clair.<P>
399 Source for a high-quality supported implementation of POP is available
400 from the <a href="ftp://ftp.qualcomm.com/eudora/servers/unix/popper/">Eudora
401 FTP site</a>. Don't use 2.5, which has a rather restrictive license.
402 The 2.5.2 version appears to restore the open-source license of
403 previous versions.<P>
406 <h2><a name="G8">G8. What is the best mail program to use with fetchmail?</a></h2>
408 Fetchmail will work with all popular <a href="#T1">mail transport programs</a>.
409 It also doesn't care which user agent you use, and user agents are as a
410 rule almost equally indifferent to how mail is delivered into your system
411 mailbox. So any of the popular Unix mail agents --
412 <a href="http://www.myxa.com/old/elm.html">elm</a>,
413 <a href="http://www.washington.edu/pine/">pine</a>
414 <a href="http://www.cs.indiana.edu/docproject/mail/mh.html">mh</a>,
415 or <a href="http://www.mutt.org">mutt</a>
416 -- will work fine with fetchmail.<p>
418 All this having been said, I can't resist putting in a discreet plug
419 for <a href="http://www.mutt.org">mutt</a>. My own personal mail
420 setup is sendmail plus fetchmail plus mutt. Mutt's interface is only
421 a little different from that of its now-moribund ancestor elm, but its
422 excellent handling of MIME and PGP put it in a class by itself. You
423 won't need its built-in POP3 support, though; most of the mutt
424 developers will cheerfully admit that fetchmail's is better :-).<p>
427 <h2><a name="G9">G9. How can I avoid sending my password en clair?</a></h2>
429 Depending on what your mail server you are talking to, this ranges
430 from trivial to impossible. It may even be next to useless.<P>
432 Most people use fetchmail over phone wires, which are hard to tap.
433 Anybody with the skill and resources to do this could get into your
434 server mailbox with much less effort by subverting the server host.
435 So if your provider setup is modem wires going straight into a service
436 box, you probably don't need to worry.<P>
438 In general there is little point in trying to secure your fetchmail
439 transaction unless you trust the security of the server host you are
440 retrieving mail from. Your vulnerability is more likely to be an
441 insecure local network on the server end (e.g. to somebody with a TCP/IP
442 packet sniffer intercepting Ethernet traffic between the modem
443 concentrator you dial in to and the mailserver host).<P>
445 Having realized this, you need to ask whether password encryption
446 alone will really address your security exposure. If you think you
447 might be snooped between server and client, it's better to use
448 end-to-end encryption on your whole mail stream so none of it can be
449 read. One of the advantages of fetchmail over conventional SMTP-push
450 delivery is that you may be able to arrange this by using ssh(1); see
451 <a href="#K3">K3</a>.<P>
453 Note that ssh is not a complete privacy solution either, as your mail
454 could have been snooped in transit to your POP server from wherever it
455 originated. For best security, agree with your correspondents to use
456 a tool such as <a href="http://www.gnupg.org/">GPG</a> (Gnu Privacy
457 Guard) or PGP (Pretty Good Privacy).<P>
459 If ssh/sshd isn't available, or you find it too complicated for you to
460 set up, password encryption will at least keep a malicious cracker
461 from deleting your mail, and require him to either tap your connection
462 continuously or crack root on the server in order to read it.<P>
464 You can deduce what encryptions your mail server has available
465 by looking at the server greeting line (and, for IMAP, the
466 response to a CAPABILITY query). Do a <code>fetchmail -v</code>
467 to see these, or telnet direct to the server port (110 for POP3, 143 for
470 The facility you are most likely to have available is APOP. This is a
471 POP3 feature supported by many servers (fetchmailconf's autoprobe
472 facility will detect it and tell you if you have it). If you see
473 something in the greeting line that looks like an
474 angle-bracket-enclosed Internet address with a numeric left-hand part,
475 that's an APOP challenge (it will vary each time you log in). You can
476 register a secret on the host (using <code>popauth(8)</code> or some
477 program like it). Specify the secret as your password in your
478 .fetchmailrc; it will be used to encrypt the current challenge, and
479 the encrypted form will be sent back the the server for
482 Alternatively, you may have Kerberos available. This may require you
483 to set up some magic files in your home directory on your client
484 machine, but means you can omit specifying any password at all.<P>
486 Fetchmail supports two different Kerberos schemes. One is a
487 POP3 variant called KPOP; consult the documentation of your mail
488 server to see if you have it (one clue is the string "krb-IV" in the
489 greeting line on port 110). The other is an IMAP facility described
490 by RFC1731. You can tell if this one is present by looking for
491 AUTH=KERBEROS_V4 in the CAPABILITY response.<P>
493 If you are fetching mail from a CompuServe POP3 account, you can use
494 their RPA authentication (which works much like APOP). See <a
495 href="#S3">S3</a> for details. If you are fetching mail from
496 Microsoft Exchange, you will be able to use NTLM.<P>
498 Your POP3 server may have the RFC1938 OTP capability to use one-time
499 passwords (if it doesn't, you can get OTP patches for the 2.2 version
500 of the Qualcomm popper from <a href="#cmetz">Craig Metz</a>). To check
501 this, look for the string "otp-" in the greeting line. If you see it,
502 and your fetchmail was built with OPIE support compiled in (see the
503 distribution INSTALL file), fetchmail will detect it also. When using
504 OTP, you will specify a password but it will not be sent en clair.<P>
506 Sadly, there is at present (September 1999) no OTP or APOP-like
507 facility generally available on IMAP servers. However, there do exist
508 patches which will OTP-enable the University of Washington IMAP
509 daemon, version 4.2-FINAL. We have a report that the GSSAPI support
510 in fetchmail works with the GSSAPI support in the most recent version
511 of UW IMAP. Or you can use <a href="#K5">SSL</a> for complete
512 end-to-end encryption if you have an SSL-enabled mailserver.<P>
514 You can get both POP3 and IMAP OTP patches from <a name="cmetz">Craig
516 href="http://www.inner.net/pub/">http://www.inner.net/pub/</a>.<P>
517 These patches use a SASL authentication method named "X-OTP" because
518 there is not currently a standard way to do this; fetchmail also uses
519 this method, so the two will interoperate happily. They better,
520 because this is how Craig gets his mail ;-)<P>
523 <h2><a name="G10">G10. Is any special configuration needed to use a dynamic IP address?</a></h2>
525 Yes. In order to avoid giving indigestion to certain picky MTAs
526 (notably <a href="#T3">exim</a>), fetchmail always makes the RCPT TO
527 address it feeds the MTA a fully qualified one with a hostname part.
528 Normally it does this by appending @ and "localhost", but when you are
529 using Kerberos or ETRN mode it will append @ and your machine's
530 fully-qualified domain name (FQDN).<P>
532 Appending the FQDN can create problems when fetchmail is running in daemon
533 mode and outlasts the dynamic IP address assignment your client
534 machine had when it started up.<P>
536 Since the new IP address (looked up at RCPT TO interpretation time)
537 doesn't match the original, the most benign possible result is that
538 your MTA thinks it's seeing a relaying attempt and refuses. More
539 frequently, fetchmail will try to connect to a nonexistent host
540 address and time out. Worst case, you could up forwarding your mail
541 to the wrong machine!<P>
543 Use the <code>smtpaddress</code> option to force the appended hostname
544 to one with a (fixed) IP address of 127.0.0.1 in your
545 <code>/etc/hosts</code>. (The name `localhost' will usually work; or
546 you can use the IP address itself).<P>
548 Only one fetchmail option interacts directly with your IP address,
549 `<code>interface</code>'. This option can be used to set the gateway
550 device and restrict the IP address range fetchmail will use. Such a
551 restriction is sometimes useful for security reasons, especially on
552 multihomed sites. See <a href="#C3">C3</a>.<P>
554 I recommend against trying to set up the <code>interface</code> option
555 when initially developing your poll configuration -- it's never
556 necessary to do this just to get a link working. Get the link working
557 first, observe the actual address range you see on connections, and
558 add an <code>interface</code> option (if you need one) later.<P>
560 If you're using a dynamic-IP configuration, one other (non-fetchmail)
561 problem you may run into with outgoing mail is that some sites will
562 bounce your email because the hostname your giving them isn't real
563 (and doesn't match what they get doing a reverse DNS on your
564 dynamically-assigned IP address). If this happens, you need to hack
565 your sendmail so it masquerades as your host. Setting<P>
571 in your <code>sendmail.cf</code> will work, or you can set<P>
574 MASQUERADE_AS(smarthost.here)
577 in the m4 configuration and do a reconfigure. (In both cases, replace
578 <code>smarthost.here</code> with the actual name of your mailhost.)
579 See the <a href="http://www.lege.com/sendmail-FAQ.txt">sendmail
580 FAQ</a> for more details.<P>
583 <h2><a name="G11">G11. Is any special configuration needed to use firewalls?</a></h2>
585 No. You can use fetchmail with SOCKS, the standard tool for
586 indirecting TCP/IP through a firewall. You can find out about SOCKS,
587 and download the SOCKS software including server and client code, at
588 the <a href="http://www.socks.nec.com/">SOCKS distribution
591 The specific recipe for using fetchmail with a firewall is at <a
595 <h2><a name="G12">G12. Is any special configuration needed to <em>send</em> mail?</a></h2>
597 A user asks: but how do we send mail out to the POP3 server? Do I need
598 to implement another tool or will fetchmail do this too?<p>
600 Fetchmail only handles the receiving side. The sendmail or other
601 preinstalled MTA on your client machine will handle sending mail
602 automatically; it will ship mail that is submitted while the
603 connection is active, and put mail that is submitted while
604 the connection is inactive into the outgoing queue.<P>
606 Normally, sendmail is also run periodically (every 15 minutes on most
607 Linux systems) in a mode that tries to ship all the mail in the
608 outgoing queue. If you have set up something like pppd to
609 automatically dial out when your kernel is called to open a TCP/IP
610 connection, this will ensure that the mail gets out.<P>
613 <h2><a name="G13">G13. Is fetchmail Y2K-compliant?</a></h2>
615 Fetchmail is fully Y2K-compliant.<P>
617 Fetchmail could theoretically have problems when the 32-bit time_t
618 counters roll over in 2038, but I doubt it. Timestamps aren't used
619 for anything but log entry generation. Anyway, if you aren't running
620 on a 64-bit machine by then, you deserve to lose.<P>
623 <h2><a name="G14">G14. Is there a way in fetchmail to support disconnected IMAP mode?</a></H2>
625 No. Fetchmail is a mail transport agent, best understood as a protocol
626 gateway between POP3/IMAP servers and SMTP. Disconnected operation
627 requires an elaborate interactive client. It's a very different problem.<p>
630 <h2><a name="G15">G15. How will fetchmail perform under heavy loads?</a></h2>
632 Fetchmail streams message bodies line-by-line; the most core it
633 ever requires per message is enough memory to hold the RFC822 header, and
634 that storage is freed when body processing begins. It is, accordingly,
635 quite economical in its use of memory.<p>
637 After startup time, a fetchmail running in daemon mode stats its
638 configuration file once per poll cycle to see whether it has changed
639 and should be rescanned. Other than that, a fetchmail in normal
640 operation doesn't touch the disk at all; that job is left up to the
641 MTA or MDA the fetchmail talks to.<p>
643 Fetchmail's performance is usually bottlenecked by latency on the POP
644 server or (less often) on the TCP/IP link to the server. This is not
645 a problem readily solved by tuning fetchmail, or even by buying more
646 TCP/IP capacity (which tends to improve bandwidth but not necessarily
650 <h2><a name="B1">B1. Lex bombs out while building the fetchmail lexer.</a></h2>
652 In the immortal words of Alan Cox the last time this came up: ``Take
653 the Solaris lex and stick it up the backside of a passing Sun
654 salesman, then install <a
655 href="ftp://ftp.gnu.org/pub/non-gnu/flex/">flex</a> and use that. All
656 will be happier.''<P>
658 I couldn't have put it better myself, and ain't going to try now.<P>
660 (The same problem has been reported under HP-UX v10.20 and IRIX)<P>
663 <h2><a name="B2">B2. I get link failures when I try to build fetchmail.</a></h2>
665 If you get errors resembling these<P>
668 mxget.o(.text+0x35): undefined referenceto `__res_search'
669 mxget.o(.text+0x99): undefined reference to`__dn_skipname'
670 mxget.o(.text+0x11c): undefined reference to`__dn_expand'
671 mxget.o(.text+0x187): undefined reference to`__dn_expand'
672 make: *** [fetchmail] Error 1
675 then you must add "-lresolv" to the LOADLIBS line in your Makefile
676 once you have installed the `bind' package.<P>
679 <h2><a name="F1">F1. Why does my old .fetchmailrc file no longer work?</a></h2>
681 <h3>If your file predates 5.1.0</h3>
683 In 5.1.0, the <tt>auth</tt> keyword and option were changed to
686 <h3>If your file predates 4.5.5</h3>
688 If the <code>dns</code> option is on (the default), you may need to
689 make sure that any hostname you specify (for mail hosts or for an SMTP
690 target) is a canonical fully-qualified hostname). In order to avoid
691 DNS overhead and complications, fetchmail no longer tries to derive
692 the fetchmail client machine's canonical DNS name at startup.<P>
694 <h3>If your file predates 4.0.6:</h3>
696 Just after the `<CODE>via</CODE>' option was introduced, I realized
697 that the interactions between the `<CODE>via</CODE>',
698 `<CODE>aka</CODE>', and `<CODE>localdomains</CODE>' options were out
699 of control. Their behavior had become complex and confusing, so much so
700 that I was no longer sure I understood it myself. Users were being
701 unpleasantly surprised.<P>
703 Rather than add more options or crock the code, I re-thought it. The
704 redesign simplified the code and made the options more orthogonal, but
705 may have broken some complex multidrop configurations.
707 Any multidrop configurations that depended on the name just after the
708 `<CODE>poll</CODE>' or `<CODE>skip</CODE>' keyword being still
709 interpreted as a DNS name for address-matching purposes, even in the
710 presence of a `<CODE>via</CODE>' option, will break.<P>
712 It is theoretically possible that other unusual configurations (such
713 as those using a non-FQDN poll name to generate Kerberos IV tickets) might
714 also break; the old behavior was sufficiently murky that we can't be
715 sure. If you think this has happened to you, contact the maintainer.<P>
717 <h3>If your file predates 3.9.5:</h3>
719 The `<code>remote</code>' keyword has been changed to `<code>folder</code>'.
720 If you try to use the old keyword, the parser will utter a warning.<P>
722 <h3>If your file predates 3.9:</h3>
724 It could be because you're using a .fetchmailrc that's written in the
725 old popclient syntax without an explicit `<CODE>username</CODE>'
726 keyword leading the first user entry attached to a server entry.
728 This error can be triggered by having a user option such as `<CODE>keep</CODE>'
729 or `<CODE>fetchall</CODE>' before the first explicit username. For
730 example, if you write<p>
733 poll openmail protocol pop3
734 keep user "Hal DeVore" there is hdevore here
737 the `<CODE>keep</CODE>' option will generate an entire user entry with
738 the default username (the name of fetchmail's invoking user).<p>
740 The popclient compatibility syntax was removed in 4.0. It complicated
741 the configuration file grammar and confused users.<p>
743 <h3>If your file predates 2.8:</h3>
745 The `<CODE>interface</CODE>', `<CODE>monitor</CODE>' and
746 `<CODE>batchlimit</CODE>' options changed after 2.8.<p>
748 They used to be global options with `<CODE>set</CODE>' syntax like the
749 batchlimit and logfile options. Now they're per-server options, like
750 `<CODE>protocol</CODE>'.<p>
752 If you had something like<p>
755 set interface = "sl0/10.0.2.15"
758 in your .fetchmailrc file, simply delete that line and insert
759 `interface sl0/10.0.2.15' in the server options part of your `defaults'
762 Do similarly for any `<CODE>monitor</CODE>' or `<CODE>batchlimit</CODE>' options.<p>
765 <h2><a name="F2">F2. The .fetchmailrc parser won't accept my all-numeric user name.</a></h2>
767 Either upgrade to a post-5.0.5 fetchmail or put string quotes around it. :-)<p>
769 The configuration file parser in older fetchmail versions treated any
770 all-numeric token as a number, which confused it when it was
771 expecting a name. String quoting forces the token's class.<p>
773 The lexical analyzer in 5.0.6 and beyond is smarter and assumes
774 any token following "username" or "password" is a string.
777 <h2><a name="F3">F3. The .fetchmailrc parser won't accept my host or username beginning with `no'.</a></h2>
779 See <a href="#F2">F2</a> You're caught in an unfortunate crack between
780 the newer-style syntax for negated options (`no keep', `no rewrite'
781 etc.) and the older style run-on syntax (`nokeep', `norewrite'
784 Upgrade to a 5.0.6 or later fetchmail, or put string quotes around your
788 <h2><a name="F4">F4. I'm getting a `parse error' message I don't understand.</a></h2>
790 The most common cause of mysterious parse errors is putting a server
791 option after a user option. Check the manual page; you'll probably
792 find that by moving one or more options closer to the `poll' keyword
793 you can eliminate the problem.<p>
795 Yes, I know these ordering restrictions are hard to understand.
796 Unfortunately, they're necessary in order to allow the `defaults'
800 <h2><a name="C1">C1. Why do I need a .fetchmailrc when running as root on my own machine?</a></h2>
802 Ian T. Zimmerman <itz@rahul.net> asked:<p>
804 On the machine where I'm the only real user, I run fetchmail as root
805 from a cron job, like this:<p>
808 fetchmail -u "itz" -p POP3 -s bolero.rahul.net
811 This used to work as is (with no .fetchmailrc file in root's home
812 directory) with the last version I had (1.7 or 1.8, I don't
813 remember). But with 2.0, it RECPs all mail to the local root user,
814 unless I create a .fetchmailrc in root's home directory containing:<p>
817 skip bolero.rahul.net proto POP3
821 It won't work if the second line is just "<CODE>user itz</CODE>". This is silly.<p>
823 It seems fetchmail decides to RECP the `default local user' (i.e. the
824 uid running fetchmail) unless there are local aliases, and the
825 `default' aliases (itz->itz) don't count. They should.<p>
829 No they shouldn't. I thought about this for a while, and I don't much
830 like the conclusion I reached, but it's unavoidable. The problem is
831 that fetchmail has no way to know, in general, that a local user `itz'
834 "Ah!" you say, "Why doesn't it check the password file to see if the remote
835 name matches a local one?" Well, there are two reasons.<p>
837 One: it's not always possible. Suppose you have an SMTP host declared
838 that's not the machine fetchmail is running on? You lose.<p>
840 Two: How do you know server itz and SMTP-host itz are the same person?
841 They might not be, and fetchmail shouldn't assume they are unless
842 local-itz can explicitly produce credentials to prove it (that is, the
843 server-itz password in local-itz's .fetchmailrc file.).<p>
845 Once you start running down possible failure modes and thinking about
846 ways to tinker with the mapping rules, you'll quickly find that all the
847 alternatives to the present default are worse or unacceptably
848 more complicated or both.<p>
851 <h2><a name="C2">C2. How can I arrange for a fetchmail daemon to get killed when I log out?</a></h2>
853 The easiest way to dispatch fetchmail on logout (which will work
854 reliably only if you have just one login going at any time) is to
855 arrange for the command `fetchmail -q' to be called on logout. Under
856 bash, you can arrange this by putting `fetchmail -q' in the file
857 `~/.bash_logout'. Most csh variants execute `~/.logout' on logout.
858 For other shells, consult your shell manual page.<p>
860 Automatic startup/shutdown of fetchmail is a little harder to arrange
861 if you may have multiple login sessions going. In the contrib
862 subdirectory of the fetchmail distribution there is some shell code
863 you can add to your .bash_login and .bash_logout profiles that will
864 accomplish this. Thank James Laferriere <babydr@nwrain.net> for
867 Some people start up and shut down fetchmail using the ppp-up and
868 ppp-down scripts of pppd.<p>
871 <h2><a name="C3">C3. How do I know what interface and address to use with --interface?</a></h2>
873 This depends a lot on your local networking configuration (and right
874 now you can't use it at all except under Linux and the newer BSDs). However,
875 here are some important rules of thumb that can help. If they don't
876 work, ask your local sysop or your Internet provider.<p>
878 First, you may not need to use --interface at all. If your machine
879 only ever does SLIP or PPP to one provider, it's almost certainly by a
880 point to point modem connection to your provider's local subnet that's
881 pretty secure against snooping (unless someone can tap your phone or
882 the provider's local subnet!). Under these circumstances, specifying
883 an interface address is fairly pointless.<p>
885 What the option is really for is sites that use more than one
886 provider. Under these circumstances, typically one of your provider
887 IP addresses is your mailserver (reachable fairly securely via the
888 modem and provider's subnet) but the others might ship your packets
889 (including your password) over unknown portions of the general
890 Internet that could be vulnerable to snooping. What you'll use
891 --interface for is to make sure your password only goes over the
894 To determine the device:<p>
897 <li> If you're using a SLIP link, the correct device is probably sl0.
898 <li> If you're using a PPP link, the correct device is probably ppp0.
899 <li> If you're using a direct connection over a local network such as
900 an ethernet, use the command `netstat -r' to look at your routing table.
901 Try to match your mailserver name to a destination entry; if you don't
902 see it in the first column, use the `default' entry. The device name
903 will be in the rightmost column.
906 To determine the address and netmask:<p>
909 <li> If you're talking to slirp, the correct address is probably 10.0.2.15,
910 with no netmask specified. (It's possible to configure slirp to present
911 other addresses, but that's the default.)
913 <li> If you have a static IP address, run `ifconfig <device>', where <device>
914 is whichever one you've determined. Use the IP address given after
915 "inet addr:". That is the IP address for your end of the link, and is
916 what you need. You won't need to specify a netmask.
918 <li> If you have a dynamic IP address, your connection IP will vary randomly
919 over some given range (that is, some number of the least significant bits
920 change from connection to connection). You need to declare an address
921 with the variable bits zero and a complementary netmask that sets
925 To illustrate the rule for dynamic IP addresses, let's suppose you're
926 hooked up via SLIP and your IP provider tells you that the dynamic
927 address pool is 255 addresses ranging from 205.164.136.1 to
928 205.164.136.255. Then<p>
931 interface "sl0/205.164.136.0/255.255.255.0"
934 would work. To range over any value of the last two octets
935 (65536 addresses) you would use<p>
938 interface "sl0/205.164.0.0/255.255.0.0"
942 <h2><a name="C4">C4. How can I set up support for sendmail's anti-spam features?</a></h2>
944 This answer covers versions of sendmail from 8.8.7 (the version
945 installed in Red Hat 5.1) upwards. If you have an older version,
946 upgrade to sendmail 8.9.<P>
948 Stock sendmails can now do anti-spam exclusions based on a database of
949 filter rules. The human-readable form of the database is at
950 <tt>/etc/mail/deny</tt>. The database itself is at
951 <tt>/etc/mail/deny.db</tt>.<P>
953 The table itself uses email addresses, domain names, and network
954 numbers as keys. For example,</P>
956 spammer@aol.com REJECT
957 cyberspammer.com REJECT
960 <P>would refuse mail from spammer@aol.com, any user from
961 cyberspammer.com (or any host within the cyberspammer.com domain), and
962 any host on the 192.168.212.* network. (This feature can be used to
963 do other things as well; see the <a
964 href="http://www.sendmail.org/m4/anti-spam.html">sendmail
965 documentation</a> for details)</P>
967 To actually set up the database, run
970 makemap hash deny <deny
974 To test, send a message to your mailing address from that host and
975 then pop off the message with fetchmail, using the -v argument. You
976 can monitor the SMTP transaction, and when the FROM address is parsed,
977 if sendmail sees that it is an address in spamlist, fetchmail will
978 flush and delete it.<p>
980 Under no circumstances put your <strong>mailhost</strong> or <strong>any host
981 you accept mail from</strong> using fetchmail into your reject file. You
982 <strong>will</strong> lose mail if you do this!!!<p>
985 <h2><a name="C5">C5. How can I poll some of my mailboxes more/less
986 often than others?</a></h2>
988 Use the <cite>interval</cite> keyword on the ones that should be
989 checked less often. For example, if you do a poll every 5 minutes,
990 and want to poll some mailboxes every 5 minutes and some every 30
991 minutes, use something like this:<p>
994 poll mainsite.example.com proto pop3 user ....
995 poll secondary.example.com proto pop3 interval 6 user ...
998 Then secondary.example.com will be polled every 6th time that
999 mainsite.example.com is polled, which with a polling interval of every
1000 5 minutes means that secondary.example.com will be polled every 30
1004 <h2><a name="C6">Fetchmail works OK started up manually, but not from an init script.</a></h2>
1006 Often, startup scripts have a different environment than an interactive
1007 login shell. For instance, $HOME might point to "/root" when you are
1008 logged in as root, but it might be either unset, or set to "/" when the
1009 startup scripts are running. That means fetchmail at startup can't find
1010 the .fetchmailrc.<p>
1012 Pick a location (such as /etc/fetchmailrc) and use fetchmail's -f
1013 option to point fetchmail at it. That should solve the problem.<p>
1016 <h2><a name="C7">C7. How can I forward mail to another host?</a></h2>
1018 To forward mail to a host other than the one you are running fetchmail
1019 on, use the <code>smtphost</code> or <code>smtpname</code> option.
1020 See the manual page for details.<p>
1023 <h2><a name="T1">T1. How can I use fetchmail with sendmail?</a></h2>
1025 For most sendmails, no special configuration is required. Eric Allman
1026 tells me that if <code>FEATURE(always_add_domain)</code> is included
1027 in sendmail's configuration, you can leave the <code>rewrite</code>
1030 If your sendmail complains ``sendmail does not relay'', make sure
1031 your sendmail.cf file says <code>Cwlocalhost</code>
1032 so that sendmail recognizes `localhost' as a name of its host.<p>
1034 If you're mailing from another machine on your local network, also
1035 ensure that its IP address is listed in ip_allow or name in name_allow
1036 (usually in /etc/mail/)<p>
1038 If you find that your sendmail doesn't like the address
1039 `FETCHMAIL-DAEMON@localhost' (which is used in the bouncemail
1040 that fetchmail generates), you may have to set
1041 <code>FEATURE(accept_unqualified_senders)</code>.<P>
1043 Günther Leber reports that Digital Unix sendmails won't work with
1044 fetchmail. The symptom is an error message "<code>553 Local configuration
1045 error, hostname not recognized as local</code>". The problem is that
1046 fetchmail normally feeds sendmail with the client machine's host
1047 address in the MAIL FROM line. These sendmails think this means
1048 they're seeing the result of a mail loop and suppress the mail. You
1049 may be able to work around this by running in <code>--invisible</code> mode.<P>
1051 If you want to support multidrop mode, and you can get access to your
1052 mailserver's sendmail.cf file, it's a good idea to add this rule:<P>
1055 H?l?Delivered-To: $h
1058 This will cause the mailserver's sendmail to reliably write the
1059 appropriate envelope address into each message before fetchmail sees
1060 it, and tell fetchmail which header it is. With this change,
1061 multidrop mode should work reliably even when the Received header
1062 omits the envelope address (which will typically be the case when
1063 the message has multiple recipients). However it will still not
1064 distinguish the recipients, your only advantage is that no bounce
1065 will be sent if a message is BCC addressed to multiple users at
1066 your site. To fix even that problem, you might want to try the
1067 following hack, which is however untested and quite experimental:<P>
1070 H?J?Delivered-To: $u
1072 Mmdrop, P=/usr/bin/procmail, F=lsDFMqSPfhnu9J,
1073 S=EnvFromSMTP/HdrFromSMTP, R=EnvToSMTP/HdrToSMTP,
1074 T=DNS/RFC822/X-Unix,
1075 A=procmail -Y -a $u -d $h
1078 For both hacks, you have to declare `<CODE>envelope "Delivered-To:"</CODE>' on
1079 the fetchmail side, to put the virtual domain (e.g. `domain.com')
1080 with RELAY permission into your access file and to add a line
1081 reading `<CODE>domain.com local:local-pop-user</CODE>' for the first and
1082 `<CODE>domain.com mdrop:local-pop-user</CODE>' for the second hack to your
1085 You will notice that if the mail already has a Delivered-To header,
1086 sendmail will not add another. Further, editing sendmail.cf
1087 directly is not very comfortable. Solutions for both problems
1088 can be found in Peter `Rattacresh' Backes' `hybrid' patch against
1089 sendmail. Have a look at it, you can find it in the contrib
1092 Feel free to try Martijn Lievaart's detailed recipe in the contrib
1093 subdirectory of the fetchmail source distribution, it attempts
1094 to realize multidrop mailboxes with an external script.<P>
1097 <h2><a name="T2">T2. How can I use fetchmail with qmail?</a></h2>
1099 Turn on the <CODE>forcecr</CODE> option; qmail's listener mode doesn't like
1100 header or message lines terminated with bare linefeeds.<p>
1102 (This information is thanks to Robert de Bath
1103 <robert@mayday.cix.co.uk>.)<p>
1105 If a mailhost is using the qmail package (see <a
1106 href="http://pobox.com/~djb/qmail.html">http://pobox.com/~djb/qmail.html</a>)
1107 then, providing the local hosts are also using qmail, it is possible
1108 to set up one fetchmail link to be reliably collect the mail for an
1111 One of the basic features of qmail is the `Delivered-To:' message
1112 header. Whenever qmail delivers a message to a local mailbox it puts
1113 the username and hostname of the envelope recipient on this line. The
1114 major reason for this is to prevent mail loops. <p>
1116 To set up qmail to batch mail for a disconnected site the ISP-mailhost
1117 will have normally put that site in its `virtualhosts' control file so
1118 it will add a prefix to all mail addresses for this site. This results
1119 in mail sent to 'username@userhost.userdom.dom.com' having a
1120 'Delivered-To:' line of the form:<p>
1123 Delivered-To: mbox-userstr-username@userhost.userdom.dom.com
1126 A single host maildrop will be slightly simpler:
1129 Delivered-To: mbox-userstr-username@userhost.dom.com
1132 The ISP can make the 'mbox-userstr-' prefix anything they choose
1133 but a string matching the user host name is likely.<p>
1135 To use this line you must:<p>
1138 <li>Ensure the option `envelope Delivered-To:' is in the fetchmail
1141 <li>Ensure you have a localdomains containing 'userdom.dom.com' or
1142 `userhost.dom.com' respectively.
1145 So far this reliably delivers messages to the correct machine of the
1146 local network, to deliver to the correct user the 'mbox-userstr-'
1147 prefix must be stripped off of the user name. This can be done by
1148 setting up an alias within the qmail MTA on each local machine.
1149 Simply create a dot-qmail file called '.qmail-mbox-userstr-default'
1150 in the alias directory (normally /var/qmail/alias) with the contents:<p>
1153 | ../bin/qmail-inject -a -f"$SENDER" "${LOCAL#mbox-userstr-}@$HOST"
1156 Note this <em>does</em> require a modern /bin/sh.<p>
1158 Peter Wilson adds: <P>
1160 ``My ISP uses "alias-unzzippedcom-" as the prefix, which means that I
1161 need to name my file ".qmail-unzzippedcom-default". This is due to
1162 qmail's assumption that a message sent to user-xyz is handled by the
1163 file ~user/.qmail-xyz (or ~user/.qmail-default).''<p>
1165 Luca Olivetti adds:<P>
1167 If you aren't using qmail locally, or you don't want to set up the
1168 alias mechanism described above, you can use the option `<code>qvirtual
1169 "mbox-userstr-"</code>' in your fetchmail config file to strip the prefix
1170 from the local user name.<p>
1173 <h2><a name="T3">T3. How can I use fetchmail with exim?</a></h2><p>
1175 If you have <CODE>rewrite</CODE> on: <P>
1177 There is an RFC1123 requirement that MAIL FROM and RCPT TO addresses
1178 you pass to it have to be canonical (e.g. with a fully qualified
1179 hostname part). Therefore fetchmail tries to pass fully qualified
1180 RCPT TO addresses. But exim does not by default accept `localhost' as
1181 a fully qualified domain. This can be fixed.<P>
1183 In exim.conf, add `localhost' to your local_domains declaration if it's not
1184 already present. For example, the author's site at thyrsus.com would
1185 have a line reading:<P>
1188 local_domains = thyrsus.com:localhost
1191 If you have <CODE>rewrite</CODE> off:<P>
1193 MAIL FROM is a potential problem if the MTAs upstream from your fetchmail
1194 don't necessarily pass canonicalized From and Return-Path addresses,
1195 and fetchmail's <CODE>rewrite</CODE> option is off. The specific case
1196 where this has come up involves bounce messages generated by sendmail
1197 on your mailer host, which have the (un-canonicalized) origin address
1200 The right way to fix this is to enable the <CODE>rewrite</CODE> option and
1201 have fetchmail canonicalize From and Return-Path addresses with the
1202 mailserver hostname before exim sees them. This option is enabled by
1203 default, so it won't be off unless you turned it off.<p>
1205 If you must run with <CODE>rewrite</CODE> off, there is a switch in exim's
1206 configuration files that allows it to accept domainless MAIL FROM
1207 addresses; you will have to flip it by putting the line <p>
1210 sender_unqualified_hosts = localhost
1213 in the main section of the exim configuration file. Note that this
1214 will result in such messages having an incorrect domain name attached
1215 to their return address (your SMTP listener's hostname rather than
1216 that of the remote mail server). <p>
1219 <h2><a name="T4">T4. How can I use fetchmail with smail?</a></h2><p>
1221 Smail 3.2 is very nearly plug-compatible with sendmail, and may work
1222 fine out of the box.<P>
1224 We have one report that when processing multiple messages from a
1225 single fetchmail session, smail sometimes delivers them in an
1226 order other than received-date order. This can be annoying because it
1227 scrambles conversational threads. This is not fetchmail's problem,
1228 it is an smail `feature' and has been reported to the maintainers
1231 Very recent smail versions require an <code>-smtp_hello_verify</code>
1232 option in the smail config file. This overrides smail's check to see
1233 that the HELO address is actually that of the client machine, which
1234 is never going to be the case when fetchmail is in the picture.
1235 According to RFC1123 an SMTP listener <em>must</em> allow this
1236 mismatch, so smail's new behavior (introduced sometime between
1237 3.2.0.90 and 3.2.0.95) is a bug.<P>
1240 <h2><a name="T5">T5. How can I use fetchmail with SCO's MMDF?</a></h2><p>
1242 MMDF itself is difficult to configure, but it turns out that
1243 connecting fetchmail to MMDF's SMTP channel isn't that hard.
1245 href="http://www.aplawrence.com/Unixart/uucptofetch.html">
1246 MMDF recipe</a> that describes replacing a UUCP link with
1247 fetchmail feeding MMDF.<P>
1250 <h2><a name="T6">T6. How can I use fetchmail with Lotus Notes?</a></h2><p>
1252 The Lotus Notes SMTP gateway tries to deduce when it should convert \n
1253 to \r\n, but its rules are not the intuitive and correct-for-RFC822
1254 ones. Use `forcecr'.<P>
1257 <h2><a name="S1">S1. How can I use fetchmail with qpopper?</a></h2>
1259 Qualcomm's qpopper is probably the best-of-breed among POP3 servers, and
1260 is very widely deployed. Nevertheless, it has some problems which
1261 fetchmail exposes. We recommend using <a href="#G7">IMAP</a> instead if at
1262 all possible. If you must talk to qpopper, here are some problems to
1265 <h3>Problems with retrieving large messages from qpopper 2.53</h3>
1267 Tony Tang <a href="mailto:tony@atn.com.hk"><tony@atn.com.hk></a>
1268 reports that there is a bad intercation between fetchmail and qpopper
1269 2.5.3 under Red Hat Linux versions 5.0 to 5.2, kernels 2.0.34 to
1270 2.0.35. When fetching very large messages (over 700K) from 2.5.3,
1271 fetchmail will hang with a socket error.<p>
1273 This is probably not a fetchmail bug, but rather a symptom of some
1274 problem in the networking stack that qpopper's transmission pattern is
1275 tickling, as fetchpop (another Linux POP client) also displays the hang
1276 but Netscape running under Win95 does not. The problem can also be
1278 href="http://www.eudora.com/freeware/qpop.html">upgrading to qpopper
1281 <h3>Bad interaction with fetchmail 4.4.2 to 4.4.7</h3>
1283 Versions of fetchmail from 4.4.2 through 4.4.7 had a bad interaction
1284 with Eudora qpopper versions 2.3 and later. See <a href="#X5">X5</a>
1285 for details. The solution is to upgrade your fetchmail.<p>
1288 <h2><a name="S2">S2. How can I use fetchmail with Microsoft Exchange?</a></h2>
1290 Fetchmail now supports the proprietary NTLM mode used with M$ Exchange
1291 servers. To enable this, configure fetchmail with the --enable-NTLM
1292 option and recompile it. Note: if you specify a user option value
1293 that looks like `user@domain', the part to the left of the @ will
1294 be passed as the username and the part to the right as the NTLM domain.<P>
1296 M$ Exchange violates the POP3 RFCs. Its LIST command does not reveal
1297 the real sizes of mail in the pop mailbox, but the sizes of the
1298 compressed versions in the exchange mail database (thanks to Arjan De
1299 Vet and Guido Van Rooij for alerting us to this problem).<P>
1301 Fetchmail works with M$ Exchange, despite this brain damage. Two
1302 features are compromised. One is that the --limit option will not
1303 work right (it will check against compressed and not actual sizes).
1304 The other is that a too-small SIZE argument may be passed to your
1305 ESMTP listener, assuming you're using one (this should not be a
1306 problem unless the actual size of the message is above the listener's
1307 configured length limit).<P>
1309 Somewhat belatedly, I've learned that there's supposed to be a
1310 registry bit that can fix this breakage:<P>
1313 HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MsExchangeIs\Parameters
1314 System\Pop3 Compatibility
1317 This is a bitmask that controls the variations from the standard protocol.
1318 The bits defined are:<P>
1322 <DD>Report exact message sizes for the LIST command
1324 <DD>Allow arbitrary linear whitespace between commands and arguments
1326 <DD>Enable the LAST command
1328 <DD>Allow an empty PASS command (needed for users with blank
1329 passwords, but illegal in the protocol)
1331 <DD>Relax the length restrictions for arguments to commands (protocol
1332 requires 40, but some user names may be longer than that).
1334 <DD>Allow spaces in the argument to the USER command.
1337 There's another one that may be useful to know about:<P>
1340 KEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MsExchangeIs\Parameters
1341 System\Pop3 Performance
1346 <DD>Render messages to a temporary stream instead of sending directly
1347 from the database (should always be on)
1349 Flag unrenderable messages (instead of just failing commands)
1350 (should only be on if you are seeing the problems reported
1353 <DD>Return from the QUIT command before all messages have been deleted.
1356 The Microsoft pod-person who revealed this information to me admitted
1357 that he couldn't find it anywhere in their public knowledge base.<P>
1359 Another specific problem we have seen with Exchange servers has as its
1360 symptom a response to LOGIN that says "NO Ambiguous Alias". Grant
1363 This means that Exchange Server is too f*&#ing stupid to figure
1364 out which mailbox belongs to you. Instead of actually keeping
1365 track of which inbox belongs to which user, it uses some
1366 half-witted, guess-o-matic heuristic to try to guess your
1367 mailbox name from your username.<p>
1369 In your case it doesn't work because your username maps to more
1370 than one mailbox. For some people it doesn't work because
1371 their username maps to zero mailboxes. This is yet another
1372 inept, lame, almost criminally negligent design decision from
1373 our friends in Redmond.<p>
1375 You've got several options:
1379 Try giving fetchmail a username of "/NTDomain/NTUsername/MailboxName".
1381 Get your administrator to configure the server so that
1382 usernames and mailbox names are the same.
1384 Get your administrator to add an alias that maps your
1385 username explicitly to your mailbox name.
1388 But, the best option involves a tactical nuclear weapon (an old
1389 ASROC will do), pissing off a lot people who live downwind from
1390 Redmond, and your choice of any Linux, NetBSD, FreeBSD, or
1393 I'll provide the CD.
1396 <h2><a name="S3">S3. How can I use fetchmail with CompuServe RPA?</a></h2>
1398 First, make sure your fetchmail has the RPA support compiled in.
1399 Stock fetchmail binaries (such as you might get from an RPM) don't.
1400 You can check this by looking at the output of <code>fetchmail -V</code>;
1401 if you see the string "+RPA" after the version ID you're good to go,
1402 otherwise you'll have to build your own from sources (see the INSTALL
1403 file in the source distribution for directions).<P>
1405 Give your CompuServe pass-phrase in lower case as your password. Add
1406 `@compuserve.com' to your user ID so that it looks like `user
1407 <UserID>@compuserve.com', where <UserID> can be either
1408 your numerical userID or your E-mail nickname. An RPA-enabled
1409 fetchmail will automatically check for csi.com in the POP server's
1410 greeting line. If that's found, and your user ID ends with
1411 `@compuserve.com', it will query the server to see if it
1412 is RPA-capable, and if so do an RPA transaction rather than a
1413 plain-text password handshake.<P>
1415 <strong>Warning:</strong> the debug (-v -v) output of fetchmail will show
1416 your pass-phrase in Unicode!<P>
1418 These two .fetchmailrc entries show the difference between an RPA and
1419 non-RPA configuration:
1422 # This version will use RPA
1423 poll csi.com via "pop.site1.csi.com" with proto POP3 and options no dns
1424 user "CSERVE_USER@compuserve.com" there with password "CSERVE_PASSWORD"
1425 is LOCAL_USER here options fetchall stripcr
1427 # This version will not use RPA
1428 poll non-rpa.csi.com via "pop.site1.csi.com" with proto POP3 and options no dns
1429 user "CSERVE_USER" there with password "CSERVE_POP3_PASSWORD"
1430 is LOCAL_USER here options fetchall stripcr
1434 <h2><a name="S4">S4. How can I use fetchmail with Demon Internet's SDPS?</a></h2>
1436 <h3>Single-drop mode</h3>
1438 You can get fetchmail to download the email for just one user from
1439 Demon Internet's POP3 server by giving it a username consisting of your
1440 Demon user name followed by your account name, with an at-sign between
1443 For example, to download email for the user <philh@vision25.demon.co.uk>,
1444 you could use the following .fetchmailrc file:<P>
1447 set postmaster "philh"
1448 poll pop3.demon.co.uk with protocol POP3:
1449 user "philh@vision25" is philh
1452 <h3>Multi-drop mode</h3>
1454 Demon Internet's SDPS service is an implementation of POP3. All messages
1455 have a Received: header added when they enter the maildrop, like this:
1458 Received: from punt-1.mail.demon.net by mailstore.com for fred@xyz.demon.co.uk
1459 id 899963657:10:27896:0; Thu, 09 Jul 98 05:54:17 GMT
1462 To enable multi-drop mode you need to tell fetchmail that 'mailstore.com' is
1463 the name of the host which accepted the mail, and let it know the
1464 hostname part(s) of your E-mail address. The following example assumes
1465 that your hostname is xyz.demon.co.uk, and that you have also bought
1466 "mail forwarding" for the domain my-company.co.uk (in which case your
1467 MTA must also be configured to accept mail sent to user@my-company.co.uk)
1470 poll pop3.demon.co.uk proto pop3 aka mailstore.com no dns:
1471 localdomains xyz.demon.co.uk my-company.co.uk
1472 user xyz is * fetchall
1475 The `fetchall' command ensures that all mail is downloaded. If you
1476 want to leave mail on the server use `uidl' and `keep'; Demon does not
1477 implement the obsolete `top' command, because SDPS combines messages
1478 residing on two separate punt clusters into a single POP3 maildrop.
1479 If you do use UIDL, be aware that the "user@host" form for fetching
1480 mail from a particular Demon host will confuse fetchmail's UIDL code;
1483 Note that Demon may delete mail on the server which is more than 30
1484 days old; see their <a
1485 href="http://www.demon.net/info/helpdesk/demon_products/mail/sdps-tech.shtml">
1486 POP3 page</a> for details.<P>
1488 <h3>The SDPS extension</h3>
1490 There's a different way to do multidrop. It's not necessary on Demon
1491 Internet, since fetchmail can parse Received addresses, but the person
1492 who implemented this didn't know that. It may be useful if Demon
1493 Internet ever changes mail transports.<P>
1495 SDPS includes a non-standard extension for retrieving the envelope of a
1496 message (*ENV), which fetchmail optionally supports if compiled with the
1497 --enable-SDPS option. If you have it, the first line of the fetchmail -V
1498 response will include the string "+SDPS".<P>
1500 Once you have SDPS compiled in, fetchmail in POP3 mode will
1501 automatically detect when it's talking to a Demon Internet host in
1502 multidrop mode, and use the *ENV extension to get an envelope To address.<P>
1504 The autodetection works by looking at the hostname in the POP3
1505 greeting line; if you're accessing Demon Internet through a proxy it
1506 may fail. To force SDPS mode, pick "sdps" as your protocol.<P>
1509 <h2><a name="S5">S5. How can I use fetchmail with usa.net's servers?</a></h2>
1511 Enable `<CODE>fetchall</CODE>'. A user reports that the 2.2 version
1512 of USA.NET's POP server reports that you must use the
1513 `<CODE>fetchall</CODE>' option to make sure that all of the mail is
1514 retrieved, otherwise some may be left on the server. This is almost
1515 certainly a server bug.<P>
1517 The usa.net servers (at least in their 2.2 version, June 1998) don't
1518 handle the TOP command properly, either. Regardless of the argument
1519 you give it, they retrieve only about 10 lines of the message.
1520 Fetchmail normally uses TOP for message retrieval in order to avoid
1521 marking messages seen, but `<CODE>fetchall</CODE>' forces it to use
1524 (Note: Other failure modes have been reported on usa.net's servers.
1525 They seem to be chronically flaky. We recommend finding another
1529 <h2><a name="S6">S6. How can I use fetchmail with HP OpenMail?</a></h2>
1531 No special configuration is required, but OpenMail versions prior to
1532 6.0 have an annoying bug similar to the big one in <a
1533 href="#S2">Microsoft Exchange</a>. The message sizes it gives in the
1534 LIST are rounded to the nearest 1024 bytes. It also has a nasty habit
1535 of discarding headers it doesn't recognize, such as X- and Resent-
1538 As with M$ Exchange, the only real fix for these problems is to get a
1539 POP (or preferably IMAP) server that isn't brain-dead. OpenMail's
1540 project manager claims these bugs have been fixed in 6.0.<P>
1543 <h2><a name="S8">S8. How can I use fetchmail with Hotmail?</a></h2>
1545 You can't, yet. But <a
1546 href="http://www.ozemail.com.au/~peterhawkins/gotmail/">gotmail</a>
1547 might be what you need.<P>
1550 <h2><a name="S9">S9. How can I use fetchmail with MSN?</a></h2>
1552 You can't. MSN uses something that looks like POP3, except the
1553 authentication part is nonstandard. And of course they don't
1554 document it, so nobody but their Windows clients can speak it.<p>
1556 This is a customer lock-in tactic; we recommend boycotting MSN as the
1557 only appropriate response.<p>
1559 As of 5.0.8, we have support for the client side of NTLM
1560 authentication. It's possible this may enable fetchmail to talk to
1561 MSN; if so, somebody should report it so this FAQ can be corrected.<p>
1564 <h2><a name="S10">S10. How can I use fetchmail with SpryNet?</a></h2>
1566 The SpryNet POP3 servers mark a message queried with TOP as seen.
1567 This means that if your connection drops in mid-message, it may end
1568 up invisibly stuck on your mail spool. Use the <code>fetchall</code>
1569 flag to ensure that it's recovered on the next cycle.<p>
1572 <h2><a name="S11">S11. How can I use fetchmail with FTGate?</a></h2>
1574 The FTGate V2 server (and possibly older versions as well) has a weird
1575 bug. It answers OK twice to a TOP request! Use the
1576 <code>fetchall</code> option to force use of RETR and work around this
1580 <h2><a name="S12">S12. How can I use fetchmail with MailMax?</a></h2>
1582 You can't. At least not if you want to be able to see attachments.
1583 MailMax has a bug; it reports the message length with attachments
1584 but doesn't download them on TOP or RETR.<P>
1586 Also, we're told that TOP sometimes fails to retrieve the entire
1587 message even when enough lines have been specified. The MailMax
1588 developers have acknowledged this bug as of 4 May 2000, but there is
1589 no fix yet. If you must use this server, force RETR with the
1590 <tt>fetchall</tt> option.<p>
1593 <h2><a name="S13">S13. How can I use fetchmail with Novell GroupWise?</a></h2>
1595 The Novell GroupWise IMAP server would be better named GroupFoolish;
1596 it is (according to the designer of IMAP) unusably broken. Among
1597 other things, it doesn't include a required content length in its
1598 BODY[TEXT] response.<p>
1600 Fetchmail works around this problem, but we strongly recommend voting
1601 with your dollars for a server that isn't brain-dead. If you stick
1602 with code as shoddy as GroupWise seems to be, you will probably pay
1603 for it with other problems.<p>
1606 <h2><a name="S14">S14. How can I use fetchmail with InterChange?</a></h2>
1608 You can't. At least not if you want to be able to see attachments.
1609 InterChange has a bug similar to the MailMax server; it reports the
1610 message length with attachments but doesn't download them on TOP or
1614 <h2><a name="K1">K1. How can I use fetchmail with SOCKS?</a></h2>
1616 Giuseppe Guerini added a --with-socks option that supports linking
1617 with socks library. If you specify the value of this option as
1618 ``yes'', the configure script will try to find the Rconnect library
1619 and set the makefile up to link it. You can also specify a directory
1620 containing the Rconnect library.<p>
1622 Alan Schmitt has added a similar --with-socks5 option that may work
1623 better if you have a recent version of the SOCKS library.
1626 <h2><a name="S7">S7. How can I use fetchmail with geocities POP3 servers?</a></h2>
1628 Nathan Cutler reports that the the mail.geocities.com POP3 servers
1629 fail to include the first Received line of the message in the send to
1630 fetchmail. This can solve problems if your MUA interprets Received
1631 continuations as body lines and doesn't parse any of the following
1634 Workaround is to use "mda" keyword or "-mda" switch:
1636 mda "sed -e '1s/^\t/Received: /' | formail | /usr/bin/procmail -d <user>"
1638 Replace \t with exactly one tabulation character.
1640 You should also consider using "fetchall" option because Geocities' servers
1641 sometimes think that the first 45 messages have already been read.<P>
1643 Fix: Get an email provider that doesn't suck. The pop-up ads on
1644 Geocities are lame, you should boycott them anyway.<P>
1647 <h2><a name="K2">K2. How can I use fetchmail with IPv6 and IPsec?</a></h2>
1649 To use fetchmail with IPv6, you need a system that supports IPv6, the "Basic
1650 Socket Interface Extensions for IPv6" (RFC 2133).
1651 This currently means that you need to have a BSD/OS or NetBSD system with
1652 the NRL IPv6+IPsec software distribution or a Linux system with the latest
1653 experimental kernel and net-tools. It should not be hard to build fetchmail on
1654 other IPv6 implementations if you can port the inet6-apps kit.<P>
1656 To use fetchmail with networking security (read: IPsec), you need a system that
1657 supports IPsec, the API described in the "Network Security API for Sockets"
1658 (draft-metz-net-security-api-01.txt), and the inet6-apps kit. This currently
1659 means that you need to have a BSD/OS or NetBSD system with the NRL IPv6+IPsec
1660 software distribution. A Linux IPsec implementation supporting this API will
1661 probably appear in the coming months.<P>
1663 The NRL IPv6+IPsec software distribution can be obtained from: <a
1664 href="http://web.mit.edu/network/isakmp">http://web.mit.edu/network/isakmp</a>
1667 The inet6-apps kit can be obtained from <a
1668 href="ftp://ftp.ipv6.inner.net/pub/ipv6">ftp://ftp.ipv6.inner.net/pub/ipv6</a>
1669 (via IPv6) or <a href="ftp://ftp.inner.net/pub/ipv6">
1670 ftp://ftp.inner.net/pub/ipv6</a> (via IPv4).<P>
1672 More information on using IPv6 with Linux can be obtained from:
1675 <a href="http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO.html">
1676 http://www.bieringer.de/linux/IPv6/IPv6-HOWTO/IPv6-HOWTO.html</a>
1678 <a href="http://www.ipv6.inner.net/ipv6">http://www.ipv6.inner.net/ipv6</a>
1681 <a href="http://www.inner.net/ipv6">http://www.inner.net/ipv6</a> (via IPv4)
1685 <h2><a name="K3">K3. How can I get fetchmail to work with ssh?</a></h2>
1687 We have five recipes for this.<P>
1689 <h3>Single-User POP3</h3>
1691 First, a lightly edited version of a recipe from Masafumi NAKANE.
1692 This one is easy to set up, but only supports one user at a time.<p>
1694 1. You must have ssh (the ssh client) on the local host and sshd (ssh
1695 server) on the remote mail server. And you have to configure ssh so
1696 you can login to the sshd server host without a password. (Refer to ssh
1697 man page for several authentication methods.)<p>
1699 2. Add something like following to your .fetchmailrc file: <p>
1702 poll mailhost port 1234 via localhost with proto pop3:
1703 preconnect "ssh -l username -f mailhost -L 1234:mailhost:110 sleep 5"
1706 The sleep is needed on slower machines to prevent fetchmail from
1707 trying to open the socket before ssh actually makes it ready. Faster
1708 machines may not need it.<p>
1710 (Note that 1234 can be an arbitrary port number. Privileged ports can
1711 be specified only by root.) The effect of this ssh command is to
1712 forward connections made to localhost port 1234 (in above example) to
1715 This configuration will enable secure mail transfer. All the
1716 conversation between fetchmail and remote pop server will be
1719 If sshd is not running on the remote mail server, you can specify
1720 intermediate host running it. If you do this, however, communication
1721 between the machine running sshd and the POP server will not be encrypted.
1722 And the preconnect line would be like this:<p>
1725 preconnect "ssh -f -L 1234:mailhost:110 sshdhost sleep 20 </dev/null >/dev/null"
1728 You can work this trick with IMAP too, but the port number 110 in the
1729 above would need to become 143. In either case you'll have to specify
1730 a password but the password will not be sent in clear.<p>
1732 There is an explanation of a similar recipe at <a
1733 href="http://sunsite.unc.edu/LDP/HOWTO/mini/Secure-POP+SSH.html">Secure
1734 POP via SSH mini-HOWTO</a>.<P>
1736 <h3>Multi-User POP3</h3>
1738 Second, a recipe from Charlie Brady <cbrady@ind.tansu.com.au>:<p>
1740 Charlie says: "The recipe [from Masafume NAKANE] certainly works, but
1741 the solution I post here is better in a few respects":
1744 <LI>this method will not fail if two or more users attempt to use fetchmail
1746 <LI>you are able to use the full facilities of tcpd to control access
1747 <LI>this method does not depend on the preconnect feature of fetchmail, so
1748 can be used for tunneling of other services as well.
1755 Make sure that the "socket" program is installed on the server
1756 machine. Presently it lives at <a
1757 href="ftp://sunsite.unc.edu/pub/linux/system/network/misc/socket-1.1.tar.gz">
1758 ftp://sunsite.unc.edu/pub/linux/system/network/misc/socket-1.1.tar.gz</a>,
1759 but watch out for a change in version number.<P>
1761 Set up an unprivileged account on your system with a .ssh directory
1762 containing an SSH identity file "identity" with no pass phrase,
1763 "identity.pub" and "known_hosts" containing the host key of your
1764 mailhost. Let's call this account "noddy".
1766 On mailhost, set up no-password access for noddy@yourhost. Add to your
1767 SSH authorized_keys file:
1770 command="socket localhost 110",no-port-forwarding 1024 ......
1773 where "<code>1024 ......</code>" is the content of noddy's identity.pub file.
1775 Create a script /usr/local/bin/ssh.fm and make it executable:
1779 exec ssh -q -C -l your.login.id -e none mailhost socket localhost 110
1782 Add an entry in inetd.conf for whatever port you choose to use - say:
1785 1234 stream tcp nowait noddy /usr/sbin/tcpd /usr/local/bin/ssh.fm
1788 Send a HUP signal to your inetd.
1791 Now just use localhost:1234 to access your POP server.<P>
1793 <h3>Multi-User IMAP</h3>
1795 This one comes comes to us from Joerg Dorchain.
1796 The basic idea is to set up a bidirectional encrypted socket connection:<p>
1799 fetchmail <--> ssh <---> sshd <--> imapd
1800 \---local side--/ \-remote side-/
1803 Use ssh-keygen(1) to set up a special ssh identity with no password
1804 and RSA-only authentication, which executes /usr/sbin/imapd when
1805 authenticated. For security reasons all other commands should be
1806 disabled. (There is some security exposure in using an identity
1807 without a passphrase; it means anyone who can get access to your
1808 account could use it to read your mail).<p>
1810 Running ssh-keygen will generate two files. Have it create the
1811 private key to ~/.ssh/identity-imap. Once you have generated the
1812 corresponding public key, prepend this to the line of key data in it:
1815 command="/usr/sbin/imapd",no-port-forwarding,no-agent-forwarding
1818 This identity data has to be appended to ~/.ssh/authorized_keys on the
1819 remote machine, as usual for RSA authentication. Whenever your ssh
1820 uses this identity, the remote side will run imapd. The imapd will
1821 see that it is not running as root and go into preauthenticated
1824 On the client side, use the <code>plugin</code> keyword to make
1825 fetchmail talk to the stdin of the remote ssh. Here's an examople:
1828 poll mail.dorchain.net
1829 with options proto imap, preauth ssh, plugin fetchmail-imap-wrapper
1832 The wrapper script should look like this:<p>
1836 exec ssh -i $HOME/.ssh/identity-imap $1 /usr/sbin/imapd
1839 <h3>Netcat-based POP or IMAP tunnelling</h3>
1841 Oren Tirosh <oren@mimique.com> sends us a method of using
1842 fetchmail over ssh without port forwarding, using the plugin keyword.<P>
1844 First, set up a poll entry resembling thius one:
1847 poll target.host plugin sshtunnel proto pop3 user foo password *
1850 The important part is the "plugin sshtunnel". Now set up sshtunnel
1854 This is the sshtunnel script:
1856 ssh $1 "nc localhost $2"
1859 Thia method uses netcat to connect to the pop3 port locally on the
1860 target host and create a two-way channel over the ssh connection.<P>
1862 Oren says: "In my experience it is much more reliable than the methods
1863 described in your FAQ. ssh port forwarding often keeps the local port
1864 bound for along timeout and has timing issues requiring tricks like
1865 sleep, etc. I use this method for fetching all the mail for
1868 <h3>Using plugin</h3>
1870 Since 5.4.5, there's been a very simple recipe. Use the following option:
1873 plugin "ssh %h /usr/sbin/rimapd"
1876 You may have to use a different absolute pathname. This option tells
1877 fetchmail that instead of opening a connection on the server's port
1878 143 and doing standard IMAP authentication, fetchmail should ssh to
1879 the server and run rimapd, using the more secure ssh authentication
1880 (as well as getting ssh's encryption).<p>
1883 <h2><a name="K4">K4. What do I have to do to use the IMAP-GSS protocol?</a></h2>
1885 Fetchmail can use RFC1731 GSSAPI authorization to safely identify you
1886 to your IMAP server, as long as you can share Kerberos V credentials
1887 with your mail host and you have a GSSAPI-capable IMAP server.
1888 UW-IMAP (available via FTP at <a
1889 href="ftp://ftp.cac.washington.edu/mail/">ftp.cac.washington.edu</a>)
1890 is the only one I'm aware of and the one I recommend anyway for other
1891 reasons. You'll need version 4.1-FINAL or greater though, and it has
1892 to have GSS support compiled in.<p>
1894 Neither UW-IMAP nor fetchmail compile in support for GSS by default,
1895 since it requires libraries from the Kerberos V distribution
1896 (available via FTP at <a
1897 href="ftp://athena-dist.mit.edu/pub/ATHENA/kerberos">athena-dist.mit.edu</a>).
1898 If you have these, compiling in GSS support is simple: add a
1899 <pre>--with-gssapi=[/path/to/krb5/root]</pre> option to configure. For
1900 instance, I have all of my Kerberos V libraries installed under
1901 /usr/krb5 so I run <pre>configure --with-gssapi=/usr/krb5</pre><p>
1903 Setting up Kerberos V authentication is beyond the scope of this FAQ
1904 (you may find Jim Rome's paper <a
1905 href="http://www.ornl.gov/~jar/HowToKerb.html"> How to Kerberize your
1906 site</a> helpful), but you'll at least need to add a credential for
1907 imap/[mailhost] to the keytab of the mail server (IMAP doesn't just
1908 use the host key). Then you'll need to have your credentials ready on
1909 your machine (cf. kinit).<p>
1911 After that things are very simple. Set your protocol to imap-gss in your
1912 .fetchmailrc, and omit the password, since imap-gss doesn't need one. You
1913 can specify a username if you want, but this is only useful if your mailbox
1914 belongs to a username different from your Kerberos principal. <p>
1916 Now you don't have to worry about your password appearing in cleartext in
1917 your .fetchmailrc, or across the network.<p>
1920 <h2><a name="K5">K5. How can I use fetchmail with SSL?</a></h2>
1922 You'll need to have the <a href="http://www.openssl.org/">OpenSSL</a>
1923 libraries installed. Configure with --with-ssl. If you have the
1924 OpenSSL libraries installed in the default location (/usr/local/ssl)
1925 this will suffice. If you have them installed in a non-default
1926 location, you'll need to specify it as an argument to --with-ssl after
1929 Fetchmail binaries built this way support <code>ssl</code>,
1930 <code>sslkey</code>, and <code>sslcert</code> options that control
1931 SSL encryption. You will need to have an SSL-enabled mailserver
1932 to use these options. See the manual page for detals.<p>
1934 If your open OpenSSL session dies with a message that complains "PRNG
1935 not seeded", update or improve your operating system. This means that
1936 the OpenSSL library on your machine has been unable to locate a source
1937 of random bits from which to seed its random-number generator;
1938 normally these come from the <tt>/dev/urandom</tt>, and this message
1939 probably means your OS doesn't have that device.<P>.
1941 An interactive program could seed the random number generator from
1942 keystroke timings or some other form of user input. Because fetchmail
1943 is primarily designed to run forever as a background daemon, that option
1944 option is not available in this case.<P>
1947 <h2><a name="R1">R1. Fetchmail isn't working, and -v shows `SMTP connect failed' messages.</a></h2>
1949 Fetchmail itself is probably working, but your SMTP port 25 listener
1950 is down or inaccessible.<p>
1952 The first thing to check is if you can telnet to port 25 on your smtp
1953 host (which is normally `localhost' unless you've specified an smtp
1954 option in your .fetchmailrc or on the command line) and get a greeting
1955 line from the listener. If the SMTP host is inaccessible or the listener
1956 is down, fix that first.<p>
1958 In Red Hat Linux 6.9, SMTP is disabled by default. To fix this,
1959 set "DAEMON=yes" in your /etc/sysconfig/sendmail file, then restart
1960 sendmail by running "/sbin/service sendmail restart".<p>
1962 If the listener seems to be up when you test with telnet, the most
1963 benign and typical problem is that the listener had a momentary seizure
1964 due to resource exhaustion while fetchmail was polling it -- process
1965 table full or some other problem that stopped the listener process
1966 from forking. If your SMTP host is not `localhost' or something else
1967 in /etc/hosts, the fetchmail glitch could also have been caused by
1968 transient nameserver failure. <p>
1970 Try running fetchmail -v again; if it succeeds, you had one of these
1971 kinds of transient glitch. You can ignore these hiccups, because a
1972 future fetchmail run will get the mail through. <p>
1974 If the listener tests up, but you have chronic failures trying to
1975 connect to it anyway, your problem is more serious. One way to work
1976 around chronic SMTP connect problems is to use --mda. But this only
1977 attacks the symptom; you may have a DNS or TCP routing problem. You
1978 should really try to figure out what's going on underneath before it
1979 bites you some other way. <p>
1981 We have one report (from toby@eskimo.com) that you can sometimes solve
1982 such problems by doing an <CODE>smtp</CODE> declaration with an IP
1983 address that your routing table maps to something other than the
1984 loopback device (he used ppp0).<p>
1986 We also have a report that this error can be caused by having an
1987 /etc/hosts file that associates your client host name with more than
1990 It's also possible that your DNS configuration isn't
1991 looking at <code>/etc/hosts</code> at all. If you're using libc5,
1992 look at <code>/etc/resolv.conf</code>; it should say something like
1998 so your <code>/etc/hosts</code> file is checked first. If you're
1999 running GNU libc6, check your <code>/etc/nsswitch.conf</code> file. Make
2000 sure it says something like
2006 again, in order to make sure <code>/etc/hosts</code> is seen first.<P>
2008 If you have a hostname set for your machine, and this hostname does
2009 not appear in /etc/hosts, you will be able to telnet to port 25 and
2010 even send a mail with rcpt to: user@host-not-in-/etc/hosts, but
2011 fetchmail can't seem to get in touch with sendmail, no matter what you
2012 set smtpaddress to.<p>
2014 We had another report from a Linux user of fetchmail 2.1 who solved his SMTP
2015 connection problem by removing the reference to -lresolv from his link
2016 line and relinking. Apparently in some older Linux distributions the
2017 libc bind library version works better.<p>
2019 As of 2.2, the configure script has been hacked so the bind library is
2020 linked only if it is actually needed. So under Linux it won't be, and
2021 this particular cause should go away.<p>
2024 <h2><a name="R2">R2. When I try to configure an MDA, fetchmail doesn't work.</a></h2>
2026 (I hear this one from people who have run into the blank-line problem in <a href="#X1">X1</a>.)<p>
2028 Try sending yourself test mail and retrieving it using the
2029 command-line options `<CODE>-k -m cat</CODE>'. This will dump exactly what
2030 fetchmail retrieves to standard output (plus the Received line
2031 fetchmail itself adds to the headers). <p>
2033 If the dump doesn't match what shows up in your mailbox when you
2034 configure an MDA, your MDA is mangling the message. If it doesn't
2035 match what you sent, then fetchmail or something on the server is
2039 <h2><a name="R3">R3. Fetchmail dumps core when given an invalid rc file.</a></h2>
2041 This is usually reported from AIX or Ultrix, but has even been known
2042 to happen on Linuxes without a recent version of <code>flex</code>
2043 installed. The problem appears to be a result of building with an
2044 archaic version of lex.<P>
2046 Workaround: fix the syntax of your .fetchmailrc file.<P>
2048 Fix: build and install the latest version of <a
2049 href="ftp://prep.ai.mit.edu/~ftp/pub/gnu">flex</a> from the Free
2050 Software Foundation. An FSF <a
2051 href="http://www.gnu.ai.mit.edu/order/ftp.html">mirror site</a>
2052 will help you get it faster.<P>
2055 <h2><a name="R4">R4. Fetchmail dumps core in -V mode, but operates normally otherwise.</a></h2>
2057 We've had this reported to us under Linux using libc-5.4.17 and gcc-2.7.2.
2058 It does not occur with libc-5.3.12 or earlier versions.<p>
2060 Workaround: link with GNU malloc rather than the stock C library malloc.<p>
2062 We're told there is some problem with the malloc() code in that
2063 version which makes it fragile in the presence of multiple free()
2064 calls on the same pointer (the malloc arena gets corrupted).
2065 Unfortunately it appears from doing gdb traces that whatever free()
2066 calls producing the problem are being made by the C library itself, not the
2067 fetchmail code (they're all from within fclose, and not an fclose called
2068 directly by fetchmail, either).<p>
2071 <h2><a name="R5">R5. Running fetchmail in daemon mode doesn't work.</a><br></h2>
2073 We have one report from a SunOS 4.1.4 user that trying to run
2074 fetchmail in detached daemon mode doesn't work, but that using the
2075 same options with -N (nodetach) is OK.<P>
2077 If this happens, you have a specific portability problem with the code
2078 in daemon.c that detaches and backgrounds the daemon fetchmail. Tell
2079 me about it so I can try to fix it. As a workaround, you can start
2080 fetchmail with -N and an ampersand to background it. A Sun user
2085 (fetchmail --nodetach <other params> &)
2088 The extra pair of parens is significant --- it makes sure that the process
2089 detaches from the initial shell (one more shell is started and dies
2090 immediately, detaching fetchmail and making it child of PID 1). This is
2091 important when you start fetchmail interactively and than quit
2092 interactive shell. The line above makes sure fetchmail lives after
2095 This should not happen under Linux or any truly POSIX-conformant Unix.<P>
2098 <h2><a name="R6">R6. Fetchmail hangs when used with pppd.</a></h2>
2100 Your problem may be with pppd's `demand' option. We have a report that
2101 fetchmail doesn't play well with it, but works with pppd if `demand'
2102 is turned off. We have no idea why this is.<p>
2105 <h2><a name="R7">R7. Fetchmail randomly dies with socket errors.</a></h2>
2107 Check the MTU value in your PPP interface reported by
2108 <code>/sbin/ifconfig</code>. If it's over 600, change it in your PPP
2109 options file. (<code>/etc/ppp/options</code> on my box). Here are
2110 option values that work:<P>
2118 <h2><a name="R8">R8. Fetchmail running as root stopped working after an OS upgrade</a></h2>
2120 In RH 6.0, the HOME value in the boot-time root environment changed
2121 from /root to / as the result of a change in init. Move your
2122 .fetchmailrc or use a -f option to explicitly point at the file.
2123 (Oddly, a similar problem has been reported from Debian systems.)<P>
2126 <h2><a name="R9">R9. Fetchmail is timing out after fetching certain
2127 messages but before deleting them</a></h2>
2129 There's a TCP/IP stalling problem under Redhat 6.0 (and possibly other
2130 recent Linuxes) that can cause this symptom. Brian Boutel writes:<p>
2133 TCP timestamps are turned on on my Linux boxes (I assume it's now the
2134 default). This uses 12 extra bytes per segment.
2135 When the tcp connection starts, the other end agrees a MSS of 1460,
2136 and then fragments 1460 byte chunks into 1448 and 12, because
2137 is is not allowing for the timestamp.<p>
2139 Then, for reasons I can't explain, it waits a long time (typically 2
2140 minutes) after the ack is sent before sending the next (fragmented)
2141 packet. Turning off tcp timestamps avoids the fragmentation and
2142 restores normal behaviour. To do this, [execute]<p>
2144 echo 0 > /proc/sys/net/ipv4/tcp_timestamps<p>
2146 I'm still unclear about the details of why this is happening. At least
2147 [now] I am now getting good performance and no queue blocking.
2151 <h2><a name="R10">R10. Fetchmail is timing out during message fetches</a></h2>
2153 This is probably a general networking issue. Sending a "RETR" command will
2154 cause the server to start sending large amounts of data, which means
2155 large packets. If your networking layer has a packet-fragmentation
2156 problem, that's where you'll see it.<p>
2159 <h2><a name="D1">D1. I think I've set up fetchmail correctly, but I'm not getting any mail.</a></h2>
2161 Maybe you have a .forward or alias set up that you've forgotten about. You
2162 should probably remove it.<p>
2164 Or maybe you're trying to run fetchmail in multidrop mode as root
2165 without a .fetchmailrc file. This doesn't do what you think it
2166 should; see question <a href="#C1">C1</a>.<p>
2168 Or you may not be connecting to the SMTP listener. Run fetchmail -v
2169 and see <a href="#R1">R1</a>.<p>
2172 <h2><a name="D2">D2. All my mail seems to disappear after a dropped connection.</a></h2>
2174 One POP3 daemon used in the Berkeley Unix world that reports itself as
2175 POP3 version 1.004 actually throws the queue away. 1.005 fixed that.
2176 If you're running this one, upgrade immediately. (It also truncates
2177 long lines at column 1024)<P>
2179 Many POP servers, if an interruption occurs, will restore the whole
2180 mail queue after about 10 minutes. Others will restore it right
2181 away. If you have an interruption and don't see it right away, cross
2182 your fingers and wait ten minutes before retrying.<P>
2184 Some servers (such as Microsoft's NTMail) are mis-designed to restore
2185 the entire queue, including messages you have deleted. If you have
2186 one of these and it flakes out on you a lot, try setting a small
2187 <code>--fetchlimit</code> value. This will result in more IP connects
2188 to the server, but will mean it actually executes changes to the queue
2191 Qualcomm's qpopper, used at many BSD Unix sites, is better behaved.
2192 If its connection is dropped, it will first execute all DELE commands as
2193 though you had issued a QUIT (this is a technical violation of
2194 the POP3 RFCs, but a good idea in a world of flaky phone lines). Then it
2195 will re-queue any message that was being downloaded at hangup time.
2196 Still, qpopper may require a noticeable amount of time to do deletions
2197 and clean up its queue. (Fetchmail waits a bit before retrying in
2198 order to avoid a `lock busy' error.)<P>
2201 <h2><a name="D3">D3. Mail that was being fetched when I interrupted my fetchmail seems to have been vanished.</a></h2>
2203 Fetchmail only sends a delete mail request to the server when either
2204 (a) it gets a positive delivery acknowledgment from the SMTP
2205 listener, or (b) it gets an error 571 (the spam-filter error) from the
2206 listener. No interrupt can cause it to lose mail.<p>
2208 However, IMAP2bis has a design problem in that its normal fetch
2209 command marks a message `seen' as soon as the fetch command to get it
2210 is sent down. If for some reason the message isn't actually delivered
2211 (you take a line hit during the download, or your port 25 listener
2212 can't find enough free disk space, or you interrupt the delivery in
2213 mid-message) that `seen' message can lurk invisibly in your server
2216 Workaround: add the `<CODE>fetchall</CODE>' keyword to your fetch options.<p>
2218 Solution: switch to an <a href="http://www.imap.org">IMAP4</a> server.<p>
2221 <h2><a name="M1">M1. I've declared local names, but all my multidrop
2222 mail is going to root anyway.</a></h2>
2224 Somehow your fetchmail is never recognizing the hostname part of
2225 recipient names it parses out of To/Cc/envelope-header lines as
2226 matching the name of the mailserver machine. To check this, run
2227 fetchmail in foreground with -v -v on. You will probably see a lot of
2228 messages with the format ``line rejected, %s is not an alias of the
2229 mailserver'' or ``no address matches; forwarding to %s.'' <p>
2231 These errors usually indicate some kind of DNS configuration problem
2232 either on the server or your client machine. <p>
2234 The easiest workaround is to add a `<CODE>via</CODE>' option (if
2235 necessary) and add enough aka declarations to cover all of your
2236 mailserver's aliases, then say `<CODE>no dns</CODE>'. This will take
2237 DNS out of the picture (though it means mail may be uncollected if
2238 it's sent to an alias of the mailserver that you don't have
2241 It would be better to fix your DNS, however. DNS problems can hurt
2242 you in lots of ways, for example by making your machines
2243 intermittently or permanently unreachable to the rest of the net.<P>
2245 Occasionally these errors indicate the sort of header-parsing problem
2246 described in <a href="#M7">M7</a>.<P>
2249 <h2><a name="M2">M2. I can't seem to get fetchmail to route to a local domain properly.</a></h2>
2251 A lot of people want to use fetchmail as a poor man's internetwork
2252 mail gateway, picking up mail accumulated for a whole domain in a single
2253 server mailbox and then routing based on what's in the To/Cc/Bcc lines.<p>
2255 In general, this is not really a good idea. It would be smarter to
2256 just let the mail sit in the mailserver's queue and use fetchmail's
2257 ETRN mode to trigger SMTP sends periodically (of course, this means
2258 you have to poll more frequently than the mailserver's expiration period).
2259 If you can't arrange this, try setting up a UUCP feed.<P>
2261 If neither of these alternatives is available, multidrop mode may do
2262 (though you <em>are</em> going to get hurt by some mailing list
2263 software; see the caveats under THE USE AND ABUSE OF MULTIDROP
2264 MAILBOXES on the man page). If you want to try it, the way to do it
2265 is with the `<CODE>localdomains</CODE>' option.<p>
2267 In general, if you use localdomains you need to make sure of two other
2270 <strong>1. You've actually set up your .fetchmailrc entry to invoke multidrop mode.</strong><p>
2272 Many people set a `<CODE>localdomains</CODE>' list and then forget
2273 that fetchmail wants to see more than one name (or the wildcard `*')
2274 in a `<CODE>here</CODE>' list before it will do multidrop routing.<p>
2276 <strong>2. You may have to set `no envelope'.</strong><p>
2278 Normally, multidrop mode tries to deduce an envelope address from a message
2279 before parsing the To/Cc/Bcc lines (this enables it to avoid losing to mailing
2280 list software that doesn't put a recipient address in the To lines).<p>
2282 Some ways of accumulating a whole domain's messages in a single server
2283 mailbox mean it all ends up with a single envelope address that is
2284 useless for rerouting purposes. You may have to set `<CODE>no
2285 envelope</CODE>' to prevent fetchmail from being bamboozled by this.<p>
2287 Check also answer <a href="#T1">T1</a> on a reliable way to do multidrop
2288 delivery if your ISP (or your mail redirection provider) is using qmail.<p>
2291 <h2><a name="M3">M3. I tried to run a mailing list using multidrop, and I have a mail loop!</a></h2>
2293 This isn't fetchmail's fault. Check your mailing list. If the list
2294 expansion includes yourself or anybody else at your mailserver (that is, not on
2295 the client side) you've created a mail loop. Just chop the host part off any
2296 local addresses in the list.<p>
2298 If you use sendmail, you can check the list expansion with
2299 <CODE>sendmail -bv</CODE>.<p>
2302 <h2><a name="M4">M4. My multidrop fetchmail seems to be having DNS problems.</a></h2>
2304 We have one report from a Linux user (not the same one as in <a
2305 href="#R1">R1</a>!) who solved this problem by removing the reference
2306 to -lresolv from his link line and relinking. Apparently in some
2307 older Linux distributions the libc5 bind library version works
2310 As of 2.2, the configure script has been hacked so the bind library is linked
2311 only if it is actually needed. So under Linux it won't be, and this problem
2315 <h2><a name="M5">M5. I'm seeing long DNS delays before each message is processed.</a></h2>
2317 Use the `<CODE>aka</CODE>' option to pre-declare as many of your
2318 mailserver's DNS names as you can. When an address's host part
2319 matches an aka name, no DNS lookup needs to be done to check it.<p>
2321 If you're sure you've pre-declared all of your mailserver's DNS names,
2322 you can use the `<CODE>no dns</CODE>' option to prevent other hostname
2323 parts from being looked up at all.<p>
2325 Sometimes delays are unavoidable. Some SMTP listeners try to call DNS
2326 on the From-address hostname as a way of checking that the address is valid.<p>
2329 <h2><a name="M6">M6. How do I get multidrop mode to work with majordomo?</a></h2>
2331 In order for sendmail to execute the command strings in the majordomo
2332 alias file, it is necessary for sendmail to think that the mail it
2333 receives via SMTP really is destined for a local user name. A normal
2334 virtual-domain setup results in delivery to the default mailbox,
2335 rather than expansion through majordomo.<P>
2337 Michael <michael@bizsystems.com> gave us a recipe for dealing
2338 with this case that pairs a run control file like this:<P>
2341 poll your.pop3.server proto pop3:
2343 localdomains virtual.localdomain1.com virtual.localdomain2.com ...
2344 user yourISPusername is root * here,
2345 password yourISPpassword fetchall
2348 with a hack on your local sendmail.cf like this:<P>
2351 #############################################
2352 # virtual info, local hack for ruleset 98 #
2353 #############################################
2355 # domains to treat as direct mapped local domain
2357 CVvirtual.localdomain1.com virtual.localdomain2.com ...
2358 ---------------------------
2360 -------------------------
2361 # handle virtual users
2363 R$+ <@ $=V . > $: $1 < @ $j . >
2364 R< @ > $+ < @ $=V . > $: $1 < @ $j . >
2365 R< @ > $+ $: $1
2366 R< error : $- $+ > $* $#error $@ $1 $: $2
2367 R< $+ > $+ < @ $+ > $: $>97 $1
2370 This ruleset just strips virtual domain names off the addresses of incoming
2371 mail. Your sendmail must be 8.8 or newer for this to work. Michael
2375 I use this scheme with 2 virtual domains and the default ISP
2376 user+domain and service about 30 mail accounts + majordomo on my
2377 inside pop3 server with fetchmail and sendmail 8.83
2381 <h2><a name="M7">M7. Multidrop mode isn't parsing envelope addresses from
2382 my Received headers as it should.</a></h2>
2384 It may happen that you're getting what appear to be well-formed
2385 sendmail Received headers, but fetchmail can't seem to extract an
2386 envelope address from them. There can be a couple of reasons for
2389 <h3>Spurious Received lines need to be skipped:</h3>
2391 First, fetchmail might be looking at the wrong Received header.
2392 Normally it looks only on the first one it sees, on the theory that
2393 that one was last added and is going to be the one containing your
2394 mailserver's theory of who the message was addressed to.<P>
2396 Some (unusual) mailserver configurations will generate extra Received
2397 lines which you need to skip. To arrange this, use the optional
2398 skip prefix argument of the `envelope' option; you may need to say
2399 something like `<code>envelope 1 Received</code>' or `<code>envelope 2
2402 <h3>The `by' clause doesn't contain a mailserver alias:</h3>
2404 When fetchmail parses a Received line that looks like
2407 Received: from send103.yahoomail.com (send103.yahoomail.com [205.180.60.92])
2408 by iserv.ttns.net (8.8.5/8.8.5) with SMTP id RAA10088
2409 for <ksturgeon@fbceg.org>; Wed, 9 Sep 1998 17:01:59 -0700
2412 it checks to see if `iserv.ttns.net' is a DNS alias of your mailserver
2413 before accepting `ksturgeon@fbceg.org' as an envelope address. This
2414 check might fail if your DNS were misconfigured, or if you were using `no dns'
2415 and had failed to declare iserv.ttns.net as an alias of your server.<P>
2418 <h2><a name="M8">M8. Users are getting multiple copies of messages.</a></h2>
2420 It's a consequence of multidrop. What's happening is that you have
2421 N users subscribed to the same list. The list software sends N
2422 copies, not knowing they will end up in the same multidrop box. Since
2423 they are both locally addressed to all N users, fetchmail delivers N
2424 copies to each user.<P>
2426 Fetchmail tries to eliminate adjacent duplicate messages in a
2427 multidrop mailbox. However, this logic depends on the message-ID
2428 being identical in both copies. It also depends on the two copies
2429 being adjacent in the server mailbox. The former is usually the case,
2430 but the latter condition sometimes fails in a timing-dependent way if
2431 the server was processing multiple incoming mail streams.
2433 I could eliminate this problem by keeping a list of all message-IDs
2434 received during a poll so far and dropping any message that matches a
2435 seen mail ID. The touble is that this is an O(N**2) operation that
2436 might significantly slow down the retriweval of large mail batches.<P>
2439 <h2><a name="X1">X1. Spurious blank lines are appearing in the headers of fetched mail.</a></h2>
2441 What's probably happening is that the POP/IMAP daemon on your
2442 mailserver is inserting a non-RFC822 header (like X-POP3-Rcpt:) and
2443 something in your delivery path (most likely an old version of the
2444 <em>deliver</em> program, which sendmail often calls to do local delivery) is
2445 failing to recognize it as a header.<p>
2447 This is not fetchmail's problem. The first thing to try is installing
2448 a current version of <em>deliver</em>. If this doesn't work, try to
2449 figure out which other program in your mail path is inserting the
2450 blank line and replace that. If you can't do either of these things,
2451 pick a different MDA (such as procmail) and declare it with the
2452 `<CODE>mda</CODE>' option.<p>
2455 <h2><a name="X2">X2. My mail client can't see a Subject line.</a></h2>
2457 First, see <a href="#X1">X1</a>. This is quite probably the same
2458 problem (X-POP3-Rcpt header or something similar being inserted by
2459 the server and choked on by an old version of <em>deliver</em>).<p>
2461 The O'Reilly sendmail book does warn that IDA sendmail doesn't process
2462 X- headers correctly. If this is your problem, all I can suggest is
2463 replacing IDA sendmail, because it's broken and not RFC822 conformant.<p>
2466 <h2><a name="X3">X3. Messages containing "From" at start of line are being split.</a></h2>
2468 If you know the messages aren't split in your server mailbox, then this
2469 is a problem with your POP/IMAP server, your client-side SMTP listener or
2470 your local delivery agent. Fetchmail cannot split messages.<p>
2472 Some POP server daemons ignore Content-Length headers and split messages on
2473 From lines. We have one report that the 2.1 version of the BSD popper
2474 program (as distributed on Solaris 2.5 and elsewhere) is broken this way.<p>
2476 You can test this. Declare an mda of `cat' and send yourself one
2477 piece of mail containing "From" at start of a line. If you see a
2478 split message, your POP/IMAP server is at fault. Upgrade to a more
2481 Sendmail and other SMTP listeners don't split RFC822 messages either.
2482 What's probably happening is either sendmail's local delivery agent or
2483 your mail reader are not quite RFC822-conformant and are breaking
2484 messages on what it thinks are Unix-style From headers. You can
2485 figure out which by looking at your client-side mailbox with vi or
2486 more. If the message is already split in your mailbox, your local
2487 delivery agent is the problem. If it's not, your mailreader is the
2490 If you can't replace the offending program, take a look at your
2491 sendmail.cf file. There will likely be a line something like<p>
2494 Mlocal, P=/usr/bin/procmail, F=lsDFMShP, S=10, R=20/40, A=procmail -Y -d $u
2497 describing your local delivery agent. Try inserting the `E' option in the
2498 flags part (the F= string). This will make sendmail turn each dangerous
2499 start-of-line From into a >From, preventing programs further downstream
2503 <h2><a name="X4">X4.</a><a name="generic_mangling">My mail is being mangled in a new and different way</a></h2>
2505 The first thing you need to do is pin down what program is doing the
2506 mangling. We don't like getting bug reports about fetchmail that are
2507 actually due to some other program's malfeasance, so please go through
2508 this diagnostic sequence before sending us a complaint.<P>
2510 There are five possible culprits to consider, listed here in the order
2511 they pass your mail:<P>
2514 <li> Programs upstream of your server mailbox.
2515 <li> The POP or IMAP server on your mailserver host.
2516 <li> The fetchmail program itself.
2517 <li> Your local sendmail.
2518 <li> Your LDA (local delivery agent), as called by sendmail or
2519 specified by <code>mda</CODE>.
2522 Often it happens that fetchmail itself is OK, but using it exposes
2523 pre-existing bugs in your downstream software, or your downstream
2524 software has a bad interaction with POP/IMAP. You need to pin down
2525 exactly where the message is being garbled in order to deduce what is
2526 actually going on.<P>
2528 The first thing to do is send yourself a test message, and retrieve it
2529 with a .fetchmailrc entry containing the following (or by running with
2530 the equivalent command-line options):<P>
2533 mda "cat >MBOX" keep fetchall
2536 This will capture what fetchmail gets from the server, except for (a)
2537 the extra Received header line fetchmail prepends, (b) header address
2538 changes due to <code>rewrite</code>, and (c) any end-of-line changes
2539 due to the <code>forcecr</code> and <code>stripcr</code> options.
2540 MBOX will in fact contain what programs downstream of fetchmail
2543 The most common causes of mangling are bugs and misconfigurations in
2544 those downstream programs. If MBOX looks unmangled, you will know
2545 that is what is going on and that it is not fetchmail's problem. Take
2546 a look at the other FAQ items in this section for possible clues about
2547 how to fix your problem.<P>
2549 If MBOX looks mangled, the next thing to do is compare it with your
2550 actual server mailbox (if possible). That's why you specified
2551 <code>keep</code>, so the server copy would not be deleted. If your
2552 server mailbox looks mangled, programs upstream of your server mailbox
2553 are at fault. Unfortunately there is probably little you can do about
2554 this aside from complaining to your site postmaster, and nothing at
2555 all fetchmail can do about it!<P>
2557 More likely you'll find that the server copy looks OK. In that case
2558 either the POP/IMAP server or fetchmail is doing the mangling. To
2559 determine which, you'll need to telnet to the server port and simulate
2560 a fetchmail session yourself. This is not actually hard (both POP3
2561 and IMAP are simple, text-only, line-oriented protocols) but requires
2562 some attention to detail. You should be able to use a fetchmail -v
2563 log as a model for a session, but remember that the "*" in your LOGIN
2564 or PASS command dump has to be replaced with your actual password.<P>
2566 The objective of manually simulating fetchmail is so you can see
2567 exactly what fetchmail sees. If you see a mangled message, then your
2568 server is at fault, and you probably need to complain to your
2569 mailserver administrators. However, we like to know what the broken
2570 servers are so we can warn people away from them. So please send
2571 us a transcript of the session including the mangling <em>and the
2572 server's initial greeting line</em>. Please tell us anything else
2573 you think might be useful about the server, like the server host's
2574 operating system.<P>
2576 If your manual fetchmail simulation shows an unmangled message,
2577 congratulations. You've found an actual fetchmail bug, which is a
2578 pretty rare thing these days. Complain to us and we'll fix it.
2579 Please include the session transcript of your manual fetchmail
2580 simulation along with the other things described in the FAQ entry on
2581 <a href="#G3">reporting bugs</a>.
2584 <h2><a name="X5">X5. Using POP3, retrievals seems to be fetching too much!</a></h2>
2586 This may happen in versions of fetchmail after 4.4.1 and before 4.4.8.
2587 Versions after 4.4.1 use POP3's TOP command rather than RETR, in order
2588 to avoid marking the message seen (leaving it unseen is helpful for
2589 later recovery if you lose your connection in the middle of a
2592 Versions of fetchmail from 4.4.2 through 4.4.7 had a bad interaction
2593 with Eudora qpopper versions 2.3 and later. The TOP bounds check was
2594 fooled by an overflow condition in the TOP argument. Decrementing the
2595 TOP argument in 4.4.7 fixed this.<P>
2597 Fix: Upgrade to a later version of fetchmail.<P>
2599 Workaround: set the <code>fetchall</code> option. Under POP3
2600 this has the side effect of forcing RETR use.<P>
2603 <h2><a name="X6">X6. My mail attachments are being dropped or mangled.</a></h2>
2605 This isn't fetchmail's doing -- fetchmail never drops lines in message
2606 bodies or attachments. It may be your POP server, or it may be the
2607 sender's mail user agent (or a bad combination of both).<p>
2609 The Mail Max POP3 server and the InterChange and Imail IMAP servers
2610 are known to simply drop MIME attachments when uploading messages.
2611 We've had sporadic reports of problems with Microsoft Exchange and
2612 Outlook servers. Windows- and NT-based POP servers seem especially
2613 prone to mangle attachments. If you are running one of these,
2614 replacing your server with a Unix machine is probably the only
2615 effective solution.<p>
2617 We've also had a report that Lotus Notes sometimes trashes the
2618 MIME type of messages. In particular, it seems to modify MIME
2619 headers introducing type application/pdf, mangling the type
2620 to application/octet-stream. It may corrupt other MIME types
2623 The IMAP service of Lotus Domino has a known bug in the way it
2624 generates MIME Content-type headers (observed on Lotus Domino 5.0.2b).
2625 It's a subtle one that doesn't show up when Netscape Messenger and
2626 other clients use a FETCH BODY[] to grab the whole message. When
2627 fetchmail uses FETCH RFC822.HEADER and FETCH RFC822.TEXT to get first
2628 the header and then the body, Domino generates different Boundary tags
2629 for each part, .e.g. one tag is declared in the Content-type header and
2630 another is used to separate the MIME parts in the body. This doesn't
2631 work. (I have heard a rumor that this bug is scheduled to be fixed
2632 in Domino release 6; you can find a workaround at contrib/domino.)<p>
2634 Another rich source of attachment problems is Microsoft Exchange and
2635 Microsoft Outlook. If you see unreadable attachments with a
2636 ContentType of "application/x-tnef", you're having this problem. The
2637 <a href="http://world.std.com/~damned/software.html">TNEF</a> utility
2640 Rob Funk explains: Unfortunately there also remain many mail user
2641 agents that don't write correct MIME messages. One big offender is Sun
2642 MailTool attachments, which are formatted enough like MIME that some
2643 programs could get confused; these are generated by the mailtool and
2644 dtmail programs (the mail programs in Sun's OpenWindows and CDE
2647 One solution to problems related to misformatted MIME attachments is
2648 the <a href="ftp://ftp.uu.se/pub/unix/networking/mail/emil/">emil</a>
2650 href="ftp://ftp.uu.se/pub/unix/networking/mail/emil/TUTORIAL.html">tutorial</a>
2651 file at that site for details on emil. It is useful for
2652 converting character sets, attachment encodings, and attachment
2653 formats. At this writing, emil does not appear to have been
2654 maintained since a patch to version 2.1.0beta9 in late 1997, but it is
2657 One good way of using emil is from within procmail. You can have
2658 procmail look for signs of problematic message formatting, and pipe
2659 those messages through emil to be fixed. emil will not always be able
2660 to fix the problem, in which case the message is unchanged.<p>
2662 A possible rule to be inserted into a .procmailrc file for using emil
2667 * 1^1 ^Content-Type: \/X-sun[^;]*
2668 * 1^1 ^Content-Type: \/application/mac-binhex[^;]*
2669 * 1^1 ^Content-Transfer-Encoding: \/x-binhex[^;]*
2670 * 1^1 ^Content-Transfer-Encoding: \/x-uuencode[^;]*
2672 LOG="Converting $MATCH
2675 | emil -A B -T Q -B BA -C iso-8859-1 -H Q -F MIME \
2676 | gawk '{gsub(/\r\n?/,"\n");print $0}'
2680 The "1^1" in the conditions is a way of specifying to procmail that if
2681 any one of the four listed expressions is found in the message, the
2682 total condition is considered true, and the message gets passed into
2683 emil. These four subconditions check whether the message has a Sun
2684 attachment, a binhex attachment, or a uuencoded attachment; there are
2685 others that could be added to check these things better and to check
2686 other relevant conditions. The "LOG=" line writes a line into the
2687 procmail log; the lone double-quote beginning the following line makes
2688 sure the log entry gets an end-of-line character. The call to gawk
2689 (GNU awk) is for fixing end-of-line conventions, since emil sometimes
2690 leaves those in the format of the originating machine; it could
2691 probably be replaced with a sed subsitution.<p>
2693 The emil call itself tries to ensure that the message uses:
2695 <li> BinHex encoding for any Apple Macintosh-only attachments
2696 <li> Quoted-Printable encoding for text (when necessary)
2697 <li> Base64 Encoding for binary attachments
2698 <li> iso-8859-1 character set for text (unfortunately emil can't yet
2699 convert from windows-1252 to iso-8859-1)
2700 <li> Quoted-Printable encoding for headers
2701 <li> MIME attachment format
2704 Most of these (the primary exceptions being the character set and the
2705 Apple binary format) are as they should be for good internet
2706 interoperability.<p>
2708 Some mail servers (Lotus Domino is a suspect here) mangle
2709 Sun-formatted messages, so the conversion to MIME needs to happen
2710 before such programs see the message. The ideal is to rid the world
2711 of Sun-formatted messages: don't use mailtool for sending attachments
2712 (it doesn't understand MIME anyway, and most of the world doesn't
2713 understand its attachments, so it really shouldn't be used at all),
2714 and make sure dtmail is set to use MIME rather than mailtool's format.<p>
2717 <h2><a name="X7">X7. Some mail attachments are hanging fetchmail.</a></h2>
2719 This isn't fetchmail's problem either; fetchmail doesn't know anything
2720 about mail attachments and doesn't treat them any differently from
2721 plain message data.<P>
2723 The most usual cause of this problem seems to be bugs in your network
2724 transport layer's capability to handle the very large TCP/IP packets
2725 that attachments tend to turn into. You can test this theory by trying to
2726 download the offending message through a webmail account; using HTTP
2727 for the message tends to simulate large-packet stress rather well, and
2728 you will probably find that the messages that seem to be choking
2729 fetchmail will make your HTTP download speed drop to zero.<P>
2731 This problem can be caused by subtle bugs in the packet-reassembly
2732 layer of your TCP/IP stack; these often don't manifest at normal
2733 packet sizes. It may also be caused by malfunctioning path-MTU
2734 discovery on the mailserver. Or, if there's a modem in the link,
2735 it may be because the attachment contains the Hayes mode escape "+++".
2738 <h2><a name="O1">O1. The --logfile option doesn't work if the logfile doesn't exist.</a></h2>
2740 This is a feature, not a bug. It's in line with normal practice for
2741 system daemons and allows you to suppress logging by removing the log,
2742 without hacking potentially fragile startup scripts. To get around
2743 it, just touch(1) the logfile before you run fetchmail (this will have
2744 no effect on the contents of the logfile if it already exists).<P>
2747 <h2><a name="O2">O2. Every time I get a POP or IMAP message the header
2748 is dumped to all my terminal sessions.</a></h2>
2750 Fetchmail uses the local sendmail to perform final delivery, which
2751 Netscape and other clients doesn't do; the announcement of new messages
2752 is done by a daemon that sendmail pokes. There should be a ``biff''
2753 command to control this. Type
2759 to turn it off. If this doesn't work, try the command
2765 which is essentially what <code>biff -n</code> will do. If this
2766 doesn't work, comment out any reference to ``comsat'' in your
2767 /etc/inetd.conf file and restart inetd.<P>
2769 In Slackware Linux distributions, the last line in /etc/profile is
2781 to solve the problem system-wide.<P>
2784 <h2><a name="O3">O3. Does fetchmail reread its rc file every poll cycle?</a></h2>
2786 No, but versions 5.2.2 and later will notice when you modify your rc
2787 file and restart, reading it.
2790 <h2><a name="O4">O4. Why do deleted messages show up again when I take
2791 a line hit while downloading?</a></h2>
2793 Because you're using a POP3 other than Qualcomm qpopper, or an IMAP
2794 with a long expunge interval.<P>
2796 According to the POP3 RFCs, deletes aren't actually performed until
2797 you issue the end-of-session QUIT command. Fetchmail cannot fix this,
2798 because doing it right takes cooperation from the server. There are
2799 two possible remedies:<P>
2801 One is to switch to qpopper (the free POP3 server from Qualcomm,
2802 the Eudora people). The qpopper software violates the POP3 RFCs by
2803 doing an expunge (removing deleted messages) on a line hangup, as well
2804 as on processing a QUIT command.<P>
2806 The other (which we recommend) is to switch to <a
2807 href="http://www.imap.org">IMAP</a>. IMAP has an explicit expunge
2808 command and fetchmail normally uses it to delete messages immediately
2809 after they are downloaded.<P>
2811 If you get very unlucky, you might take a line hit in the window
2812 between the delete and the expunge. If you've set a longer expunge
2813 interval, the window gets wider. This problem should correct itself
2814 the next time you complete a successful query.<P>
2817 <h2><a name="O5">O5. Why is fetched mail being logged with my name, not the real From address?</a></h2>
2819 Because logging is done based on the address indicated by the sending
2820 SMTP's MAIL FROM, and some listeners are picky about that address.<p>
2822 Some SMTP listeners get upset if you try to hand them a MAIL FROM
2823 address naming a different host than the originating site for your
2824 connection. This is a feature, not a bug -- it's supposed to help
2825 prevent people from forging mail with a bogus origin site. (RFC 1123
2826 says you shouldn't do this exclusion...)<p>
2828 Since the originating site of a fetchmail delivery connection is
2829 localhost, this effectively means these picky listeners will barf on
2830 any MAIL FROM address fetchmail hands them with an @ in it!<p>
2832 Versions 2.1 and up try the header From address first and fall back to
2833 the calling-user ID. So if your SMTP listener isn't picky, the log
2837 <h2><a name="O6">O6. I'm seeing long sendmail delays or hangs near the start of each poll cycle.</a></h2>
2839 Sendmail does a hostname lookup when it first starts up, and also each
2840 time it gets a HELO in listener mode.<p>
2842 Your resolver configuration may be causing one of these lookups to
2843 fail and time out. Check <code>/etc/resolv.conf</code> and
2844 <code>/etc/hosts</code> file. Make sure your hostname and
2845 fully-qualified domain name are both in <code>/etc/hosts</code>, and
2846 that hosts is looked at before DNS is queried. You probably also want
2847 your remote mail server(s) to be in the hosts file.<p>
2849 You can suppress the startup-time lookup if need to by reconfiguring
2850 with <code>FEATURE(nodns)</code>.<p>
2852 Configuring your bind library to cache DNS lookups locally may help,
2853 and is a good idea for speeding up other services as well. Switching to
2854 a faster MTA like qmail or exim might help. <p>
2857 <h2><a name="O7">O7. Why doesn't fetchmail deliver mail in date-sorted order?</a></h2>
2859 Because that's not the order the server hands it to fetchmail in.<P>
2861 Fetchmail getting mail from a POP server delivers mail in the order
2862 that your server delivers mail. Fetchmail can't do anything about
2863 this; it's a limitation of the underlying POP protocol.<P>
2865 In theory it might be possible for fetchmail in IMAP mode to sort
2866 messages by date, but this would be in violation of two basics of
2867 fetchmail's design philosophy: (a) to be as simple and transparent a
2868 pipe as possible, and (b) to <em>hide</em>, rather than emphasize, the
2869 differences between the remote-fetch protocols it uses.<P>
2871 Re-ordering messages is a user-agent function, anyway.<P>
2874 <h2><a name="O8">O8. I'm using pppd. Why isn't my monitor option working?</a></h2>
2876 There is a combination of circumstances that can confuse fetchmail.
2877 If you have set up demand dialing with pppd, and pppd has an idle
2878 timeout, and you have lcp-echo-interval set, then the
2879 lcp-echo-interval time must be longer than the pppd idle timeout.
2880 Otherwise it is going keep increasing the packet counters that fetchmail
2881 relies upon, triggering fetchmail into polling after its own delay
2882 interval and thus preventing the pppd link from ever reaching its
2883 inactivity timeout.<p>
2886 <h2><a name="O9">O9. Why does fetchmail keep retrieving the same messages
2887 over and over?</a></h2>
2889 First, check to see that you haven't enabled the <cite>keep</cite>
2890 and <cite>fetchall</cite> option. If you have, turn <cite>keep</cite> off.<p>
2892 There are various forms of lossage involving the POP3 UIDL feature
2893 that can lead to all your old messages being seen again after a line
2894 drop. I have given up trying to fix these, as the UIDL code breaks
2895 worse every time I touch it. The problem is fundamental; maintaining
2896 and garbage-collecting the right kind of client-side state is just
2897 hard. Whoever put UIDLs in RFC1725 and removed LAST should be hung
2898 up by his thumbs and whipped with scorpions. The right answers are
2899 either (a) live with the occasional breakage, (b) switch to IMAP4,
2900 or (c) fix the code yourself and send me a patch. Unless you choose
2901 (c), I don't want to hear about it.<p>
2903 This can also happen when some other mail client is logged in to your
2904 mail server, if it uses a simple exclusive-locking scheme (and many,
2905 especially most POP3 servers, do exactly that). Your fetchmail is
2906 able to retrieve the messages, but because the mailbox is write-locked
2907 by the other instance yours can neither mark messages seen or delete them.
2908 The solution is to either (a) wait for the other client to finish, or (b)
2911 James Stevens <James.Stevens@kyzo.com> writes:<p>
2914 We had a Linux box dialing the Net and collecting mail from an NT POP3
2915 server. Fetchmail was correctly collecting and deleting each e-mail
2916 one by one. However,the dial-up connection was very unreliable and
2917 would often just drop out in the middle of a session.<p>
2919 Interestingly, unless the TCP POP3 connection was terminated normally
2920 (I guess with a POP3 "QUIT" command) NT would then roll back all the
2923 This meant if the first e-mail was very large it might just end up
2924 continuously collecting it, basically jamming the queue. Or, if the
2925 queue became very full itmight never get a long enough phone
2926 connection to retrieve the entire mailbox, and NT would roll back any
2927 deletes, so it would end up collecting (and delivering) the first few
2928 e-mails again and again. As the POP3 mailbox became fuller and fuller
2929 the chances of getting a connection long enough to collect theentire
2930 mailbox became smaller and smaller.<p>
2932 Our solution was to make fetchmail only collect a few (say 5 or 10)
2933 e-mails at atime, thus trying to ensure that the POP3 connection is
2934 terminated correctly.
2937 That's one solution. Perhaps a better one would be to FORMAT C: and
2938 install Linux on your server...<p>
2941 <table width="100%" cellpadding=0><tr>
2942 <td width="30%">Back to <a href="index.html">Fetchmail Home Page</a>
2943 <td width="30%" align=center>To <a href="/~esr/sitemap.html">Site Map</a>
2944 <td width="30%" align=right>$Date: 2000/11/11 18:20:46 $
2947 <P><ADDRESS>Eric S. Raymond <A HREF="mailto:esr@thyrsus.com"><esr@snark.thyrsus.com></A></ADDRESS>
2952 compile-command: "(cd ~/WWW; upload fetchmail/fetchmail-FAQ.html)"
projects / ~andy / fetchmail / blob