Situation: the client is running RD Services on Windows 2012 and the licensing seems to be configured correct. RD Licensing Diagnoser or Get-RDLicenseConfiguration don’t show any errors.
However, remote users receive this message when accessing the RD server: “The remote session was disconnected because there are no remote Desktop License Servers available to provide a licence”.
Troubleshooting: Even they have 5 users login the RD Server, but the RD licensing manager shows all licenses are available and no licensees are used.
No remote Desktop Licence Server availible on RD Session Host server 2012 – 360ICT – Technical Blog
The solution was to delete the REG_BINARY in
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Terminal Server\RCM\GracePeriod