We have a 2003 Server which is also a Domain controller which is acting as our Terminal Services license server which is set to Domain discovery mode. The server is activated and We have 2003 Per device CALS installed and the terminal servers are set to point to the license server by a GPO and are all set to per device mode. When checking Everything appears to be working fine it is issueing both permant CALS and temp cals and there is plenty of licenses available but every now and then we get issues with clients where they get an error that "The remote session was diconnected because there are no terminal server license servers available to provide a license" we can fix this issue by delete the mslicensing registry keys on the clients but this is not a permant fix to the problem
We also have a 2008R2 TSlicensing server in the same domain which is activated and has 2008 R2 per device CALS installed this is also set to per device on all the 2008 R2 Terminal servers
Can someone explain why this issue occurs ? and is there a permant fix to this issue ?