outlook 2016 on Mac - "Mailbox already exists" error.

Anonymous
2016-10-06T05:13:04+00:00

Error "mailbox already exists (0.000 + 0.000 secs)" - and outlook loses connection to IMAP server (shows empty account).

Then, either through manual intervention (clicking on another account and then coming back), or sometimes it just does it by itself, it "rediscovers" my IMAP mailbox and works OK... Until next time (falls over every ?? 30 minutes or so).

Using outlook 2016 on Mac, V15.26.1. This also happened on previous version.

Didnt used to be a problem. Just started about 2 weeks ago with no changes from my end that I am aware of!?! Upgraded to latest Version today. Made no difference.

Advice welcome!

Outlook | MacOS | Legacy Outlook for Mac | For business

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  1. Anonymous
    2017-06-27T21:50:59+00:00

    The Office 365 update last week (approx June 21, 2017 solved my Outlook issues. Try to update again if you haven't done so in the past week.

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  2. Anonymous
    2017-06-27T21:49:25+00:00

    No problem.  Unfortunately my update is that even after switching to IMAP Idle, and Outlook for Mac working well for about 2 hours this morning, the same error still reared it's ugly head:

    Mailbox Already Exists

    Even before it crashed, I'm not sure it was working well enough.  Seems like it was taking too long for folders to update or for me to be notified of new unread messages in folders.  

    After the 4th time in 4 days during a busy work day, I've officially given up on Outlook for Mac.  Typical Microsoft quality I guess.  I bought a Mac to get away from Microsoft, and now I remember why.  

    I'm on to Mac Mail.  I don't like how Mac Mail separates your Inbox, and I don't like that there are no keyboard commands for moving messages (in Outlook you CMD + SHIFT + M then type your folder name and press Enter).

    But Mac Mail is superior in many other ways.

    • easier scheduling in iCal
    • easier addition of contacts stores in iCloud
    • view attachments in-line in body of email without having to click or open them
    • clearer organization of replies and forwards on email thread
    • faster, smoother, more reliable, has never crashed
    • emails send and receive/appear very quickly
    • drag and drop to move emails to folders is faster and smoother than Outlook

    So while it doesn't "look" as pretty, it at least works.  So I'm making due.  It's not worth spending any more time deleting and adding my accounts in Outlook just to keep getting this stupid "Mailbox Already Exists" error which cripples the entire email client.  

    The Office 365 update last week (June 21 approx) solved all my Outlook issues. If you haven't tried this latest update, try to update again. Worked for me. Back to loving Outlook!

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  3. Anonymous
    2017-06-27T21:46:56+00:00

    Happy to report that the last Office 365 update week of June 21, 2017 solved my problems with Outlook. Try the latest update!

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