We use Rebex to access mails of outlook account using OAuth tokens retrieved from login live API. From last week outlook IMAP server returns "NO Authenticate failed" error code. We update the token retrieval to Microsoft Graph APIs. Even then IMAP responds similarly.
Geeks support is highly appreciated.
Regards, Arun. S
This should be helpful now , OAuth IMAP Auth support ... didn't used to work, but should now.
https://learn.microsoft.com/en-us/exchange/client-developer/legacy-protocols/how-to-authenticate-an-imap-pop-smtp-application-by-using-oauth