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
    2017-06-01T19:10:33+00:00

    Same with me!  About 2 months both with my Macbook Air and my iMac.

    Reloads the IMAP inbox all day long and gives me the errors.

    I double-checked my settings and everything is ligit!

    I'm on 365 with 10.12.2 Sierra.

    Tried a new Outlook profile, tried regenerating the account, at my wit's end...

    I've had this problem for several months now. Microsoft techies spent 3 hrs, uninstalled, reinstalled Office 2016, etc and still no success. All day losing IMAP emails and redownloading them. But only with my Comcast 3 accounts. Gmail works perfectly. The comcast accounts work on the iphone and ipad, and windows 10 pc so doesn't seem to be provider issue. Seems to be Outlook for Mac (Office 365) problem. Very irritating. Researched all kinds of things online before contacting Microsoft and nothing worked for me. I'm using latest Sierra 10.12.4.

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  2. Anonymous
    2017-02-20T01:57:49+00:00

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

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  3. Anonymous
    2017-02-19T19:23:15+00:00

    Exactly!

    I suspect, as I think you said in a previous post, that it has something to do with a mismatch or corruption of some type between the client and the server.

    I have two IMAP emails set up on Outlook, one of them was continuing to have the issue even after I removed most of the emails from it, so just now I removed ALL the emails from it.

    I suspect without any emails to confuse it, there will be no more error messages and/or disappearance of folders...

    We will see....as I start to receive emails on that account....it will be interesting to see how long it takes for the issue to appear again, and I'm hoping that's a VERY long time!

    Thanks ever so much for your suggestions, Dale!!

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  4. Anonymous
    2017-02-19T17:54:00+00:00

    It seems to be a syncing issue. So I guess it ca happen in any account but the bigger it is the more likely it is to have an issue between the two databases.

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  5. Anonymous
    2017-02-19T15:41:59+00:00

    I deleted or archived most of the email in my IMAP accounts that I'm accessing with Outlook for Mac 2016, and so far, that seems to have fixed the issue.

    What I wonder is, when will it start happening again?

    i understand that the fewer emails I have accessible to Outlook, the lower the chances of the issue, but do we know what triggers it??

    Thanks!

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