Remote desktop gateway failing giving a 0x500003 error to clients

Saw NPS error and saw this in the Event Log of the NPS event log:

Log Name: System
Source: NPS
Date: 26/01/2021 15:02:03
Event ID: 4402
Task Category: None
Level: Error
Keywords: Classic
User: N/A
Computer: server.domain.local
Description:
There is no domain controller available for domain domain.
Event Xml:



4402
2
0
0x80000000000000

137208
System
server.domain.local



domain



I had to go into NPS applet and right click NPS server root in GUI and choose 'register server with active directory'

Yes the NPS server cannot find the domain or domain controller until you click 'register with active directory' in the root of the NPS user interface to register the server and service with AD.

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