[Dovecot] All mail in mbox disappears when using Outlook

[Frank Leonhardt]

This was sent on Saturday but didn't make it to the list (possibly a problem
my end).

Incidentally, I've since restarted Dovecot to see if that helped. It didn't.

Luigi Rosa wrote on 01 August 2009 14:10
> Frank Leonhardt said the following on 01/08/09 12:00:
> 
> > I've searched as far as I can for any known problems using Outlook.
> 
> What about the size of the mailbox?
> 
> Each version of Outlook has its own issue regarding the maximum size of
> PST files.

Good guess knowing Outlook, and a good question as I'd forgot to mention it,
but these are IMAP mailboxes, and they're therefore 'cached' in individual
.pst files for each box. Originally I'd suspected it was a size issue with
Dovecot as it worked when I split the files, but I now know that simply
copying the files is enough. FWIW the problem mbox files are ~100M on the
server - nothing exceptional.

Incidentally, having had much experience of Outlook, 2Gb is a good working
assumption (32-bit signed addressing). This was the official limit in
earlier versions (pre-Unicode), but if you reached it, big trouble.
Personally I never let them get to more than 1.5Gb. Outlook 2003 is an
interesting case - standard PST files are Unicode but those used for caching
IMAP are ASCII, so you still have the limit to worry about. I believe the
physical limit was removed in Outlook 2007 - the upper limit is now set in
the registry at a default of ~20Gb - but creating bigger files is still bad
news as you'll either wreck a Microsoft filing system somewhere or need to
import the file into an older version of Outlook (or data recover tool).