The fix we have used for “the remote session was disconnected because there are no remote desktop license servers available to provide a license” on Windows Server 2012 is to have the server look for the IP of the license server and not the server name.
For a single Remote Desktop Server which Is NOT connected to a domain setting the group policy “Use the specified Remote Desktop license servers” to the IP address of the server instead of the server name fixes the connection error.
To change this setting to the IP we use GPEdit.msc
Browse down to the key under:
Local Computer Policy
Remote Desktop Services
Remote Desktop Session Host
Then in right hand pane – double click “Use the specified Remote Desktop license servers”
This should be “enabled” and in the text box under “License servers to use” enter the IP of the server “xxx.123.123.123”
We then forced a Group Policy restart and also rebooted the server AND it still took about 20 minutes before the users could again login to the Terminal Server / Remote Desktop Server.
This assumes you have licensing installed and configured for your Remote Desktop Users.
Including “Specify the licensing mode for the RD Session Host Server” as Per Device or Per User.