- dovecot - dovecot.org

[Dovecot] changing fs separator for maildir (suggestions?)
by Justin McAleer 05 Apr '07

05 Apr '07

Since we're migrating from an existing system that allows periods in folder names, I believe we must continue to allow them. So, I am deciding what to use as the separator instead. Right now, I'm leaning towards the backtick (`), since I don't think I have ever used it unless I was trying to execute an external command in some code. So, can anybody think of reasons not to use it, or have a better idea?

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Re: [Dovecot] Problems using GFS2 and clustered dovecot
by David Craigon 05 Apr '07

05 Apr '07

Well, I'm not paying for it. And I've managed to fix the comedy stability I've come across so far, but you're right- I haven't really loaded the system up yet. My rationale is that I want a filesystem I can share between several servers, reducing the points of failure as far as I can down. We've got a large iSCSI SAN we've already bought for other projects, and I'd like to use that for our storage. So using NFS, I'd have to have another server in front of my SAN that act as an NFS server (presuambly as a single point of failuire), and the mail servers as NFS clients. I'd rather have the servers talk to the SAN directly. Besides, NFS never really works for me, but I'm sure I could overcome that. Anyway, I don't think it's a GFS problem so far. David > -----Original Message----- > From: dovecot-bounces(a)dovecot.org > [mailto:dovecot-bounces@dovecot.org] On Behalf Of Justin McAleer > Sent: 05 April 2007 13:37 > To: dovecot(a)dovecot.org > Subject: Re: [Dovecot] Problems using GFS2 and clustered dovecot > > David Craigon wrote: > > I am trying to use dovecot. I've got a GFS2 shared volume on two > > servers with dovecot running on both. On one server at a > time, it works. > > > > > > Sorry to not answer your question directly, but do you have a > good reason to be using GFS instead of NFS? We experimented > with GFS last year (granted, not GFS2), and found its > performance pretty horrible and its stability comically > bad... had we been paying for it, however, it wouldn't have > been funny. OCFS2 was better, but still unreliable. Lustre > was the best we found (it worked, at least), but it required > a lot of hardware/admin overhead. We tried other clustering > filesystems as well, and none of them was worth the trouble. > > > The test I am trying is to attach two mail programs (MUA) via IMAPS > > (Thunderbird and Evolution as it happens). I've attached one mail > > program to each IMAPS server. I am trying to move emails > around in one > > program (from folder to folder), and then checking it on the other > > program. I'm testing in effect how it would work if my users log on > > twice and end up on different servers. > > > > I seem to suffer from never ending index file corruption: > > > > Apr 4 16:55:49 mailstore-b dovecot: > > IMAP(david(a)everybody-loves.craigon.co.uk): Corrupted > transaction log > > file > > > /mnt/mailstore/e/everybody-loves.craigon.co.uk/d/david/.fish/dovecot.i > > nd > > ex.log: > > end_offset (284) > current sync_offset (104) Apr 4 16:55:49 > > mailstore-b > > dovecot: > > IMAP(david(a)everybody-loves.craigon.co.uk): broken sync positions in > > index file > > > /mnt/mailstore/e/everybody-loves.craigon.co.uk/d/david/.fish/dovecot.i > > nd > > ex > > Apr 4 16:55:49 mailstore-b dovecot: > > IMAP(david(a)everybody-loves.craigon.co.uk): fscking index file > > > /mnt/mailstore/e/everybody-loves.craigon.co.uk/d/david/.fish/dovecot.i > > nd > > ex > > Apr 4 16:55:49 mailstore-b dovecot: > > IMAP(david(a)everybody-loves.craigon.co.uk): Fixed index file > > > /mnt/mailstore/e/everybody-loves.craigon.co.uk/d/david/.fish/dovecot.i > > nd > > ex: > > log file sync pos 1,284 -> 1, 104 > > Apr 4 16:55:50 mailstore-b dovecot: > > IMAP(david(a)everybody-loves.craigon.co.uk): Unexpected > transaction log > > desync with index > > > /mnt/mailstore/e/everybody-loves.craigon.co.uk/d/david/.fish/dovecot.i > > nd > > ex > > Apr 4 16:56:18 mailstore-b dovecot: > > IMAP(david(a)everybody-loves.craigon.co.uk): Transaction log file > > > /mnt/mailstore/e/everybody-loves.craigon.co.uk/d/david/.fish/dovecot.i > > nd > > ex.log: > > marked corrupted > > > > This happens pretty quickly. I can also get message > duplication- if I > > move a message from one server to another, I can get a > message in the > > original folder and the destination folder. > > > > I am using RC28. I have tried using fcntl locking and > dotlocking with > > equal lack of success. > > > > Can anyone offer any advice? > > > > David > > > > > > Griffin Information Systems Ltd > > 20 St Christopher's Way, > > Pride Park, > > Derby > > DE24 8JY > > www.griffin.com <http://www.griffin.com/> > > > > Registered in England and Wales. Company Registration > Number: 3676297. > > VAT Number: 716604053 > > > > > > > > >

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Re: [Dovecot] Problems using GFS2 and clustered dovecot
by David Craigon 05 Apr '07

05 Apr '07

Sorry, it's just struck me that I've missed out the most important information- I am using maildir++. Sorry :-(. The index files are kept on the shared volume. And to answer the other question again, mmap is off. David > -----Original Message----- > From: Andrey Panin [mailto:pazke@donpac.ru] > Sent: 05 April 2007 10:25 > To: David Craigon > Cc: dovecot(a)dovecot.org > Subject: Re: [Dovecot] Problems using GFS2 and clustered dovecot > > On 095, 04 05, 2007 at 09:58:44AM +0100, David Craigon wrote: > > I am trying to use dovecot. I've got a GFS2 shared volume on two > > servers with dovecot running on both. On one server at a > time, it works. > > > > The test I am trying is to attach two mail programs (MUA) via IMAPS > > (Thunderbird and Evolution as it happens). I've attached one mail > > program to each IMAPS server. I am trying to move emails > around in one > > program (from folder to folder), and then checking it on the other > > program. I'm testing in effect how it would work if my users log on > > twice and end up on different servers. > > > > I seem to suffer from never ending index file corruption: > > Where are index files located ? > > > Apr 4 16:55:49 mailstore-b dovecot: > > IMAP(david(a)everybody-loves.craigon.co.uk): Corrupted > transaction log > > file > > > /mnt/mailstore/e/everybody-loves.craigon.co.uk/d/david/.fish/dovecot.i > > nd > > ex.log: > > end_offset (284) > current sync_offset (104) Apr 4 16:55:49 > > mailstore-b > > dovecot: > > IMAP(david(a)everybody-loves.craigon.co.uk): broken sync positions in > > index file > > > /mnt/mailstore/e/everybody-loves.craigon.co.uk/d/david/.fish/dovecot.i > > nd > > ex > > Apr 4 16:55:49 mailstore-b dovecot: > > IMAP(david(a)everybody-loves.craigon.co.uk): fscking index file > > > /mnt/mailstore/e/everybody-loves.craigon.co.uk/d/david/.fish/dovecot.i > > nd > > ex > > Apr 4 16:55:49 mailstore-b dovecot: > > IMAP(david(a)everybody-loves.craigon.co.uk): Fixed index file > > > /mnt/mailstore/e/everybody-loves.craigon.co.uk/d/david/.fish/dovecot.i > > nd > > ex: > > log file sync pos 1,284 -> 1, 104 > > Apr 4 16:55:50 mailstore-b dovecot: > > IMAP(david(a)everybody-loves.craigon.co.uk): Unexpected > transaction log > > desync with index > > > /mnt/mailstore/e/everybody-loves.craigon.co.uk/d/david/.fish/dovecot.i > > nd > > ex > > Apr 4 16:56:18 mailstore-b dovecot: > > IMAP(david(a)everybody-loves.craigon.co.uk): Transaction log file > > > /mnt/mailstore/e/everybody-loves.craigon.co.uk/d/david/.fish/dovecot.i > > nd > > ex.log: > > marked corrupted > > > > This happens pretty quickly. I can also get message > duplication- if I > > move a message from one server to another, I can get a > message in the > > original folder and the destination folder. > > > > I am using RC28. I have tried using fcntl locking and > dotlocking with > > equal lack of success. > > > > Can anyone offer any advice? > > > > David > > > > > > Griffin Information Systems Ltd > > 20 St Christopher's Way, > > Pride Park, > > Derby > > DE24 8JY > > www.griffin.com <http://www.griffin.com/> > > > > Registered in England and Wales. Company Registration > Number: 3676297. > > VAT Number: 716604053 > > > > > > > > -- > Andrey Panin | Linux and UNIX system administrator > pazke(a)donpac.ru | PGP key: wwwkeys.pgp.net >

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Re: [Dovecot] Problems using GFS2 and clustered dovecot
by David Craigon 05 Apr '07

05 Apr '07

Yes > -----Original Message----- > From: Tomi Hakala [mailto:tomi.hakala@pobox.fi] > Sent: 05 April 2007 11:30 > To: David Craigon > Cc: dovecot(a)dovecot.org > Subject: Re: [Dovecot] Problems using GFS2 and clustered dovecot > > On Thu, 2007-04-05 at 09:58 +0100, David Craigon wrote: > > I am trying to use dovecot. I've got a GFS2 shared volume on two > > servers with dovecot running on both. On one server at a > time, it works. > > Do you have mmap disabled? > > Tomi > >

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[Dovecot] solaris 10 dovecot-1.0.rc29 - building issue
by Davide Vaghetti 05 Apr '07

05 Apr '07

Hi all, I'm having terrible time, and a lot of core dumps, building dovecot on Solaris 10. My environment: gcc 3.3.2 LDFLAGS=-L/usr/local/ssl/lib -lssl -lcrypto \ -L/usr/local/BerkeleyDB.4.2/lib -ldb -L/usr/local/lib -lldap CPPFLAGS=-I/usr/local/BerkeleyDB/include \ -I/usr/local/include -I/usr/local/ssl/include my configure: ./configure --prefix=/usr/local --with-ldap ...that is: Install prefix ...................... : /usr/local File offsets ........................ : 64bit I/O loop method ..................... : poll File change notification method ..... : none Building with SSL support ........... : yes (OpenSSL) Building with IPv6 support .......... : yes Building with pop3 server ........... : yes Building with mail delivery agent .. : yes Building with GSSAPI support ........ : no Building with user database modules . : static prefetch passwd passwd-file checkpassword ldap (modules) Building with password lookup modules : passwd passwd-file shadow pam checkpassword ldap (modules) Building with SQL drivers ............: When I try to actually make it, this is the result: Making all in imap make[3]: Entering directory `/usr/local/src/dovecot-1.0.rc29/src/imap' /bin/ksh ../../libtool --tag=CC --mode=link gcc -std=gnu99 -g -O2 -Wall -W -Wmissing-prototypes -Wmissing-declarations -Wpointer-arith -Wchar-subscripts -Wformat=2 -Wbad-function-cast -export-dynamic -L/usr/local/ssl/lib -L/usr/local/BerkeleyDB.4.2/lib -L/usr/local/lib -o imap cmd-append.o cmd-capability.o cmd-check.o cmd-close.o cmd-copy.o cmd-create.o cmd-delete.o cmd-examine.o cmd-expunge.o cmd-fetch.o cmd-idle.o cmd-list.o cmd-logout.o cmd-lsub.o cmd-namespace.o cmd-noop.o cmd-rename.o cmd-search.o cmd-select.o cmd-sort.o cmd-status.o cmd-store.o cmd-subscribe.o cmd-thread.o cmd-uid.o cmd-unselect.o cmd-unsubscribe.o client.o commands.o commands-util.o imap-expunge.o imap-fetch.o imap-fetch-body.o imap-messageset.o imap-search.o imap-sort.o imap-sync.o imap-thread.o mail-storage-callbacks.o main.o namespace.o ../lib-storage/register/libstorage-register.a ../../src/lib-storage/index/maildir/libstorage_maildir.a ../../src/lib-storage/index/mbox/libstorage_mbox.a ../../src/lib-storage/index/dbox/libstorage_dbox.a ../../src/lib-storage/index/libstorage_index.a ../../src/lib-index/libindex.a ../lib-storage/libstorage.a ../lib-storage/subscription-file/libstorage_subscription_file.a ../lib-imap/libimap.a ../lib-mail/libmail.a ../lib-dict/libdict.a ../lib-charset/libcharset.a ../lib/liblib.a ../lib/mountpoint.o /usr/local/lib/libiconv.so -L/usr/openwin/lib -R/usr/local/lib -export-dynamic -lsocket -lnsl -lrt -lsendfile gcc -std=gnu99 -g -O2 -Wall -W -Wmissing-prototypes -Wmissing-declarations -Wpointer-arith -Wchar-subscripts -Wformat=2 -Wbad-function-cast -o imap cmd-append.o cmd-capability.o cmd-check.o cmd-close.o cmd-copy.o cmd-create.o cmd-delete.o cmd-examine.o cmd-expunge.o cmd-fetch.o cmd-idle.o cmd-list.o cmd-logout.o cmd-lsub.o cmd-namespace.o cmd-noop.o cmd-rename.o cmd-search.o cmd-select.o cmd-sort.o cmd-status.o cmd-store.o cmd-subscribe.o cmd-thread.o cmd-uid.o cmd-unselect.o cmd-unsubscribe.o client.o commands.o commands-util.o imap-expunge.o imap-fetch.o imap-fetch-body.o imap-messageset.o imap-search.o imap-sort.o imap-sync.o imap-thread.o mail-storage-callbacks.o main.o namespace.o ../lib/mountpoint.o /usr/local/lib/libiconv.so -L/usr/local/ssl/lib -L/usr/local/BerkeleyDB.4.2/lib -L/usr/local/lib ../lib-storage/register/libstorage-register.a ../../src/lib-storage/index/maildir/libstorage_maildir.a ../../src/lib-storage/index/mbox/libstorage_mbox.a ../../src/lib-storage/index/dbox/libstorage_dbox.a ../../src/lib-storage/index/libstorage_index.a ../../src/lib-index/libindex.a ../lib-storage/libstorage.a ../lib-storage/subscription-file/libstorage_subscription_file.a ../lib-imap/libimap.a ../lib-mail/libmail.a ../lib-dict/libdict.a ../lib-charset/libcharset.a ../lib/liblib.a -L/usr/openwin/lib -lsocket -lnsl -lrt -lsendfile -R/usr/local/lib make[3]: *** [imap] Bus Error (core dumped) make[3]: *** Deleting file `imap' make[3]: Leaving directory `/usr/local/src/dovecot-1.0.rc29/src/imap' make[2]: *** [all-recursive] Error 1 make[2]: Leaving directory `/usr/local/src/dovecot-1.0.rc29/src' make[1]: *** [all-recursive] Error 1 make[1]: Leaving directory `/usr/local/src/dovecot-1.0.rc29' make: *** [all] Error 2 I tried the rc27 and rc28 too with the same results. Does anybody experienced similar issues ? thanks in advance bye -- Davide Vaghetti Centro SerRA - University of Pisa NOC

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Re: [Dovecot] compiling dovecot on aix gcc 3.3.2
by Ralf Becker 05 Apr '07

05 Apr '07

Hello funkypunky drunky, on AIX dovecot plugins (which are shared objects = .so) are a little bit problematic. It is not enough to activate run time linking by using -brtl and make the main program (dovecot) to be able to use shared objects. When a share object does function calls back into the main program, all these functions (=symbols) in dovecot have to be explicitly exported. Otherwise you see "signal 11" or so. Because this is very fiddly, there is a linker flag -bexpall to export all symbols of the main program (dovecot)... but this does seemingly not work with symbols defined in static libraries (.a). While dovecot build creates static libraries to keep the linker command line small, but does *not* generate export files (.exp) containing the libraries globals symbols, the compile time linker does not known anything about them. I think, if dovecot build would use libtool to create the libraries, libtool would export the libraries symbols to fix this. And this is, what my script does. It looks on the compiler command line for library file (.a) and exports all global symbols to an .exp file. The paths of these .exp files are appended to the original compiler command line and so -bexpall knows about the globale symbols defined in the libraries and is able to export them. I don't know if this information is useful for you, because you're using gcc. But if you are using AIX ld (instead of gnu ld) you have to deal with this problem, I think. Regards, Ralf funkypunky drunky schrieb: > Hi Ralf > I check your script. But i cannot udnerstand what you do. R u trying to > export the library of the dovecot? I cannot go deeper. Anyway would you > like to tell what did you do with XLC compiler. Maybe i can setup the > analogy of it when using gcc instead of XLC. > Best regards. > > > 2007/3/27, Ralf Becker <beckerr(a)fh-trier.de <mailto:beckerr@fh-trier.de>>: > > Hello! > > Have you tried to export all symbols defined in lib archives generated > while dovecot is build? I've had this problem on aix with xlC and > solved > it by writing an compiler script for doing that. > > See > http://www.dovecot.org/list/dovecot/2007-February/019226.html > and > http://wiki.dovecot.org/AixPluginsSupport > > Regards, Ralf > > Timo Sirainen schrieb am 26.03.2007 21:08: > > On Mon, 2007-03-26 at 09:24 +0300, funkypunky drunky wrote: > >> I pasted the output of gdb. I hope it is usefull. Thanx > >> > >> This GDB was configured as "powerpc-ibm-aix5.1.0.0"... > >> Core was generated by `imap'. > >> Program terminated with signal 11, Segmentation fault. > >> #0 0xd1a468cc in i_malloc () > >> from /usr/local/lib/dovecot/imap/lib10_quota_plugin.so > >> (gdb) bt full > >> #0 0xd1a468cc in i_malloc () > >> from /usr/local/lib/dovecot/imap/lib10_quota_plugin.so > >> No symbol table info available. > >> #1 0xd1a47cc8 in quota_init () at quota.c:32 > > > > So it crashes at the first Dovecot function it tries to call. Perhaps > > the imap binary isn't exporting the symbols, or something like that. > > I've no idea. Anyway it is most likely related to some linking or > > compiling flags (or the linker/compiler itself). > > > > -- > ______________________________________________________________________ > > Dipl.-Inform. (FH) Ralf Becker Rechenzentrum (r/ft) der FH Trier > (Network|Mail|Web|Firewall) University of applied sciences > Administrator Schneidershof, D-54293 Trier > > Mail: beckerr(a)fh-trier.de > <mailto:beckerr@fh-trier.de> Fon: +49 651 8103 499 > WWW: http://www.fh-trier.de/~beckerr Fax: +49 651 8103 214 > PGP: http://www.fh-trier.de/~beckerr/pgp ICQ: <available> > ______________________________________________________________________ > > Wenn Gott gewollt haette, dass E-Mail in HTML geschrieben wuerden, > endeten Gebete traditionell mit </amen>. (Tom Listen) > > -- ______________________________________________________________________ Dipl.-Inform. (FH) Ralf Becker Rechenzentrum (r/ft) der FH Trier (Network|Mail|Web|Firewall) University of applied sciences Administrator Schneidershof, D-54293 Trier Mail: beckerr(a)fh-trier.de Fon: +49 651 8103 499 WWW: http://www.fh-trier.de/~beckerr Fax: +49 651 8103 214 PGP: http://www.fh-trier.de/~beckerr/pgp ICQ: <available> ______________________________________________________________________ Wenn Gott gewollt haette, dass E-Mail in HTML geschrieben wuerden, endeten Gebete traditionell mit </amen>. (Tom Listen)

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[Dovecot] 1.0.rc29 released
by Timo Sirainen 05 Apr '07

05 Apr '07

http://dovecot.org/releases/dovecot-1.0.rc29.tar.gz http://dovecot.org/releases/dovecot-1.0.rc29.tar.gz.sig Probably one more RC after this. * Security fix: If zlib plugin was loaded, it was possible to open gzipped mbox files outside the user's mail directory. + Added auth_gssapi_hostname setting. - IMAP: LIST "" "" didn't return anything if there didn't exist a namespace with empty prefix. This broke some clients. - If Dovecot is tried to be started when it's already running, don't delete existing auth sockets and break the running Dovecot - If deliver failed too early it still returned exit code 89 instead of EX_TEMPFAIL. - deliver: INBOX fallbacking with -n parameter wasn't working. - passdb passwd and shadow couldn't be used as master or deny databases - IDLE: inotify didn't notice changes in mbox file - If index file directory couldn't be created, disable indexes instead of failing to open the mailbox. - Several other minor fixes

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[Dovecot] IMAP Admin Software ?
by Azher Amin 04 Apr '07

04 Apr '07

Hi, I am looking for IMAP Admin Software that can help me managing the accounts and quota , aliases on the local server. My installation is: - Linux - Dovecot 1.0 rc28 I tried using the openwebmail but it is giving errors in the php scripts. Plz suggest. -Azher -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.

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[Dovecot] --with-vpopmail compile errors
by Oliver Schulze L. 04 Apr '07

04 Apr '07

Hi, I'm building dovecot.src.rpm with vpopmail support and I get this error: if gcc -DHAVE_CONFIG_H -I. -I. -I../.. -I../../src/lib -I../../src/lib-sql -I../../src/lib-settings -I../../src/lib-ntlm -DAUTH_MODULE_DIR=\""/usr/lib/dovecot/auth"\" -DPKG_LIBEXECDIR=\""/usr/libexec/dovecot"\" -I/home/vpopmail/include -std=gnu99 -O2 -g -march=i686 -Wall -W -Wmissing-prototypes -Wmissing-declarations -Wpointer-arith -Wchar-subscripts -Wformat=2 -Wbad-function-cast -I/usr/kerberos/include -std=gnu99 -O2 -g -march=i686 -Wall -W -Wmissing-prototypes -Wmissing-declarations -Wpointer-arith -Wchar-subscripts -Wformat=2 -Wbad-function-cast -I/usr/kerberos/include -MT userdb-vpopmail.o -MD -MP -MF ".deps/userdb-vpopmail.Tpo" -c -o userdb-vpopmail.o userdb-vpopmail.c; \ then mv -f ".deps/userdb-vpopmail.Tpo" ".deps/userdb-vpopmail.Po"; else rm -f ".deps/userdb-vpopmail.Tpo"; exit 1; fi userdb-vpopmail.c: In function `vpopmail_lookup_vqp': userdb-vpopmail.c:30: error: `auth_request' undeclared (first use in this function) userdb-vpopmail.c:30: error: (Each undeclared identifier is reported only once userdb-vpopmail.c:30: error: for each function it appears in.) make[3]: *** [userdb-vpopmail.o] Error 1 make[3]: Leaving directory `/usr/src/redhat/BUILD/dovecot-1.0.rc27/src/auth' make[2]: *** [all-recursive] Error 1 make[2]: Leaving directory `/usr/src/redhat/BUILD/dovecot-1.0.rc27/src' make[1]: *** [all-recursive] Error 1 make[1]: Leaving directory `/usr/src/redhat/BUILD/dovecot-1.0.rc27' make: *** [all] Error 2 error: Bad exit status from /var/tmp/rpm-tmp.73126 (%build) I'm using: - vpopmail from: http://www.qmailtoaster.com/download/stable/vpopmail-toaster-5.4.13-1.3.3.s… - centos 4.4 - dovecot rpm from: http://dl.atrpms.net/all/dovecot-1.0-3_50.rc27.at.src.rpm - rpmbuild command: rpmbuild --rebuild --without inotify --with pam_stack --with forcequota2 --with vpopmail --target=i686 dovecot-1.0-3_50.rc27.at.src.rpm Also, I don't if vpopmail support is official, in that case, this info should go to the devel version of dovecot HTH Oliver -- Oliver Schulze L. | Get my e-mail after a captcha in: Asuncion - Paraguay | http://tinymailto.com/oliver

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[Dovecot] *****SPAM***** The folder 'Inbox' cannot contain items. Namespace problems
by Francisco Reyes 04 Apr '07

04 Apr '07

Several attempts to support both Mac and PCs keep failing. In my latest attempt I used the following settings: #courier-imap compatibility/Thunderbird namespace private { separator = . prefix = INBOX. inbox = yes } For MAC OS Mail.app namespace private { separator = / prefix = INBOX/ inbox = no hidden= yes } This last attempt was based on the suggestion of Timo Sirainen, on the Mac settings. The PC settings were the defaults I got from the sample config and have always worked for PC clients. The new setup with namespace private worked for Mac clients, but got the following error for a number of users in both Outlook and thunderbird. Unable to display the folder. The folder 'Inbox' cannot contain items. This is most likely a limitation of your IMAP server. In order to create a folder that can contain items, be sure to append / to its name as you create it. I see this is an old issue. http://groups.google.com/group/microsoft.public.outlook/browse_thread/thread /5f990142171fb792/62adb6c069946e40?lnk=st&q=%22cannot+contain+items%22+dovec ot&rnum=1#62adb6c069946e40 One interesting point we discovered was that if we set an IMAP account in Outlook the very first time we logged in, it worked. If we closed the client, all subsequent times the "folder Inbox cannont contain items" error would come up. doing a TCPdump showed us that the difference was that the first time that Outlook connects it issued a "Select" command, but all other times it did not. Someone suggested to take out prefix = INBOX. Would that help? I don't want to cause problems for the vast majority of our PC users while trying to fix the Mac clients. Even though Mac users are a minority of our users, it is extremely problematic for us not to be able to support them because many domains may have a handfull of such clients.. so we basically will not be able to host a large number of domains in dovecot machines, just because of a handfull of Mac clients. Currently using Dovecot r27, but have been having this same problem since r15.

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