Log tells everything: [12:41:05] * message: Account '*************': Connecting to IMAP4 server: 10.0.1.15... [12:41:05] IMAP4< * OK Microsoft Exchange Server 2003 IMAP4rev1 server version 6.5.7638.1 (*************) ready. [12:41:05] * message: IMAP connection is un-authenticated [12:41:09] IMAP4> 1 CAPABILITY [12:41:09] IMAP4< * CAPABILITY IMAP4 IMAP4rev1 IDLE LOGIN-REFERRALS MAILBOX-REFERRALS NAMESPACE LITERAL+ UIDPLUS CHILDREN [12:41:09] IMAP4< 1 OK CAPABILITY completed. [12:41:09] IMAP4> Logging ************* to 10.0.1.15 using LOGIN [12:41:09] IMAP4< CAPABILITY completed. [12:41:09] ** warning: IMAP error on 10.0.1.15: stream error [12:41:09] ** warning: IMAP4 connection broken [12:41:09] IMAP4< Error logging in to 10.0.1.15 Permanent stream error during login. Other MUA (e.g. Thunderbird) works well with same settings (IMAP over SSL on port 993 with plain LOGIN auth). Other IMAP account works well (dovecot IMAP).
Which libetpan version is Claws Mail using?
Name : libetpan16 Version : 1.1 Release : 2.1.2 Architecture: x86_64
I also see this frequently. Bug hunting at work on the Exchange Server indicates a very high probability for a bug in the Exchange 2007 Imap implementation. dpkg -s libetpan15 Package: libetpan15 Status: install ok installed Priority: optional Section: libs Installed-Size: 831 Maintainer: Nikita V. Youshchenko <yoush@debian.org> Architecture: amd64 Source: libetpan Version: 1.0-5
Hi, well, that's no surprise, it's replying with the previous reply with the sequence number and the OK: [12:41:09] IMAP4< 1 OK CAPABILITY completed. [12:41:09] IMAP4> Logging ************* to 10.0.1.15 using LOGIN [12:41:09] IMAP4< CAPABILITY completed. That doesn't make any sense. Libetpan is strict in its IMAP implementation and that's by design, so I doubt their developers would want to introduce uncertainty and hacks for the purpose of making broken servers work...
For others searching for solution, issue (or better: "feature request") at libetpan github: https://github.com/dinhviethoa/libetpan/issues/45