
I have numerous other Outlook 2016 clients configured and working (installed as older versions, but have been updated), so I used those to troubleshoot (same scenario, domain joined on internal LAN and external WAN). Check Autodiscover DNS entries, InternalURL and ExternalURL configurationĪll the of the above came back fine and were configured properly.Check Virtualdirectory configuration on IIS (Internet Information Services).Check Virtualdirectory configuration on Exchange.This was on the internal LAN on a domain joined workstation. In the latest updates and versions of Microsoft Office 2016, I found a bug where when a user adds a new on-premise Microsoft Exchange 2016 account, it will repeatedly prompt for a username and password and ultimately fail if you hit cancel (no matter how many times you enter credentials).
