remote desktop licensing mode is not configured

With Server 2019, if you are not using a Windows Domain, you can get the error message

//remote desktop licensing mode is not configured

remote destkop services will stop working in 107 days. On the RD Connection Broker server, use Server Manager to specify the Remote Desktop…//

This is difficult to track down, but basically turns out that you must configure localhost (the machine you're on) to be the license server. You can only do this in a per device licensing mode.

Following two are pretty decent explainations. The second (a Youtube Video with no sound) does a walk through.