The symptom I saw was Outlook would not connect to Office 365 Online Exchange because it wouldn't do modern authentication. We had to force it to use IMAP. This failed after a week.
https://docs.microsoft.com/en-us/outlook/troubleshoot/authentication/continually-prompts-password-office-365
Download and run this tool: https://aka.ms/SaRA-OutlookPwdPrompt
It fixed the issue, set up a new Outlook profile with modern authentication, no more issues.
Keywords: Outlook 2013, 2016, Forgets, lost, password, exchange, imap |