Set:
unmanaged PC
Windows 10
MS Outlook 2019
Microsoft Exchange E-Mail
Problem:
cannot login with d\uaccount, or...
...
no connection possible, or...
something in that vein.
Solution:
Click on the Windows "Start" button
...
reboot the PC
start Outlook
Problems after the FIX:
Outlook may just work fine now, or you geht an error message in the form of "VC**** not installed, cannot open Outlook..."
...
start Outlook
Outlook should work now