One user reported that after changing the visibility of IMAP folders, they started receiving this error. The same settings worked on Apple Mail and other variations of Outlook and other e-mail clients. This issue was specifically triggered in Outlook 2011. To resolve this issue, you will need to delete and re-add account as IMAP.
Disable POP After you have finished these steps, Close Outlook, restart your machine and open Outlook. All the messages from the server will be downloaded again, and the account should now work fine.
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