So you go to RDP into a server and this lovely message:
Let me tell you, after rebooting a clients server for a RAID update I was greated with this, on their DC. I wanted to just go home.
The troopoer that I am I used GOOOOGGGLLLEE who found the answer:
Edit the registry of the affected machine. Go to
HKLM\SYSTEM\CurrentControlSet\Control\Terminal Server
Create a new DWord "IgnoreRegUserConfigErrors" (no quotes) and edit it as a decimal and make the value one. That should get you connected in.