Forum Discussion
Office 365 + Outlook 2016 random weird login issues?
That's probably a request to some on-premises resource. Are you in Hybrid? Are the users accessing any shared calendars, or maybe syncing SharePoint lists, etc? What happens if you cancel the prompt - does Outlook stay connected? Generally speaking, the easier way to get an answer to this is to run a Fiddler trace once the prompts start appearing.
We are Hybrid for AD-AAD but not for Exchange. The people who have problems don't have any shared calendars or lists other than Office 365 groups. They are rarely accessing the groups. If they cancel the prompt outlook won't connect. If they try to input password it goes away and doesn't connect and then pops up again almost instantly.
Sometimes if they reboot computer it fixes it, but often not. It simply seems to be wait the problem out and it goes away.
