On 03/06/2018 01:51 PM, Jerry wrote:

George,

    We run Dovecot with Outlook, and have had similar problems when Outlook is operating in "Offline Mode". When you're in offline mode, doing any folder-level operations, such as Copy, Create, Rename, Move, Delete, etc. causes problems with the mailbox. The end result is that you could lose e-mails and entire folders that were involved in the offline operation.

    How we have fixed this in the past, what we have done is:
  1. Do an Outlook "export" of the entire contents of the IMAP account into a ".pst" file. (This saves the e-mails that may be at-risk of being lost.)
  2. Delete the IMAP account in Outlook, which includes the ".ost" file.
  3. Delete the IMAP account on the Dovecot server
  4. Reconfigure the IMAP account in Outlook
  5. Restore the IMAP contents from the ".pst" file in step #1.
  6. Educate the user about not doing folder-level operations while in offline mode.
    Hope this helps...

Thanks,
John

I did as you state above with a little variation and it works thanks for the hint. My
changed sequence is (for anyone with same trouble) :

1. Export the mails into a pst (while off-line) . Don't be alarmed if you DON'T see some of your messages
in the pst afterwards it's another bug we have to thank MS for, you have to change the default view
to IMAP  on some folders to see the emails (go figure why you have to do so in a pst...)

2. Delete the ost used by the account (or rename it if you wish, just to be sure) .
3. Let outlook refetch all messages from the server again ( to be sure I counted the
size of the users maildir on the folder  and waited for the ost to come close and report no more
downloading, close one or two times outlook to be sure).
4. Import the previous pst back into outlook with the no duplicates option .

After that the mailbox was in sync with no mail missing. I just hope that was a one time glitch but to be sure
I instructed the user to be cautious while working from home and report if he sees signs
of  not syncing . I'm not confident though that it will not happen again .

On Tue, 6 Mar 2018 10:22:36 +0100, Jakob Curdes stated:

Thanks,

that means that outlook is useless as an Imap client then . This is 
the whole idea behind
imap, to be able to do work while off-line and sync changes when 
on-line or I get it wrong ?

thanks anyway  
I would see it a bit more general: Outlook is mostly useless as email 
client in general (not looking at the groupware functionality). Even 
with Exchange or other server types, many simple things do not work 
reliably and never get fixed.
And the simplest things are impossible, e.g. displaying the full email 
address of a sender instead of the name only (to make it harder to spoof 
senders). I suspect 2016 is the 2nd-last version of Outlook to be 
released and from then on it will be browser-only.
That said, IMAP support is "strange" and has always been - OL trusts its 
own .ps ort .ost file more than the server which circumvents the general 
idea of IMAP. If you need Outlook, avoid IMAP and if you need IMAP, 
avoid Outlook....

JC
What version of Outlook are you using? I have "2016 (16.0.9029.2016) 32-bit
installed and it does not exhibit the problems that you allege it does?

mine Is a fresh o365 subscription without exchange. The user is allowed to
install on his laptop to work at home.


Have you ever tried any of the MS Forums?

https://social.technet.microsoft.com/Forums/en-US/home
https://answers.microsoft.com/en-us/msoffice/forum/msoffice_outlook
http://answers.microsoft.com/en-us/office/forum/outlook

I think  the forums you describe above is mostly a waste of time.  You cannot find
much of useful info on them (that's me personal opinion of course but ... )


There are others of course, and I have had good success in the past getting
answers. In my experience, the source of the problem is usually PEBKAC.


PEBKAC might be but Outlook MUST behave as an email client , otherwise drop support
for IMAP and POP3 and state that it's only for exchange (but this way they will loose $$$ i guess).

Sorry for the long reply

George