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
    2017-06-02T16:48:24+00:00

    Same problem here, just purchased Office 2016, 365 and my mailbox clears out and I need to redownload after seeing that same message. Fortunately I only have 500 emails now, but I get lots of emails a day and it's annoying to have to constantly re-download 3-4 times per day!!!

    Unacceptable. I stick to Outlook b/c people at work use that too, but if I really have to I will stop my 365 subscription and move to Mac Mail. My Office 2011 worked like a charm.

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  2. Anonymous
    2017-06-05T14:20:19+00:00

    Add my name to the list of people that are dealing with this problem. For me it's my Comcast account. There are no emails in any folders in my Comcast account and I have the latest version of Outlook 2016.

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  3. Anonymous
    2017-06-06T18:47:18+00:00

    Same issue here, on 2 separate Macs using 2 different Office365 subscriptions. So I doubt formatting would make any difference at all, it's clearly a problem with Outlook itself :(

    My setup:

    2 IMAP accounts, 1 has the problem and the other does not

    less than 10 emails in inbox

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  4. Anonymous
    2017-06-06T20:00:34+00:00

    I concur.  The archive has not worked for me either.  Mac Mail might be the solution for this comcast account. 

    This is not a size issue for me. I don't have that many emails. And 2 of the 3 problem email accounts have single digit number of emails. Gmail works on the imac.  3 comcast imap accounts don't. Those non working accounts work perfectly on my iphone, ipad, and windows 10 pc (pc uses outlook 365). Only office 365 for mac outlook is the problem. Profile not the problem. Version not the problem since i have had on 2 versions now. Definitely a sync issue. Microsoft totally doesn't care about Mac users. If Apple could improve its software we could all dump outlook.

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  5. Jim G 134.1K Reputation points MVP
    2017-06-08T15:33:44+00:00

    Please go to the Outlook menu and choose About Outlook, and then reply with the version you have. Thanks.

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