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
    2017-06-08T16:59:13+00:00

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

    Computer Details...

    Computer: MacBook Pro (13-inch, Mid 2012)

    Operating System: macOS Sierra, Version 10.12.5

    Hardware: 2.9 GHz Intel Core i7, 8GB DDR3 @ 1600 MHz, Samsung SSD 850 EVO 1TB

    **Software:**2016 Microsoft Office 365, Version 15.34 (170515)

    This is the most annoying thing ever. Emails keep disappearing and have to re-download them ALL. As my inbox count goes up, this is going to be a worse problem. I use MacMail for personal emails and Outlook for work email.

    It would suck to have to merge both and solely rely on MacMail, will unsubscribe from Office 365 and reinstall my copy of 2011 if this doesn't get resolved soon.

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  2. Anonymous
    2017-06-08T17:05:35+00:00

    As I mentioned in my previous email, a suggestion to extend time to 15minutes on sync... after 1 week, the problem has not resurfaced.

    SOLVED!

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  3. Anonymous
    2017-06-08T19:19:44+00:00

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

    Sorry. Out of town. It is definitely latest version as of last week because i checked for updates and there were none.

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  4. Anonymous
    2017-06-15T00:20:09+00:00

    I must say, I set my accounts to check for mail less frequently, with a time of 15 minutes, and the problem appears to have disappeared! 

    Very nice!

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  5. Anonymous
    2017-06-15T01:43:25+00:00

    As I mentioned in my previous email, a suggestion to extend time to 15minutes on sync... after 1 week, the problem has not resurfaced.

    SOLVED!

    Well as the post above me agrees and I must say myself I set the time to 10 minutes and the problem seems to be less frequent. I haven't noticed it happening since, but I didn't pay close close attention to truly keep track. I'll write back but must say it has seemed to help.

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