When backing up a license server, back up both the System State data and the folder in which the TS Licensing database is installed. This ensures that data in both the registry and the TS Licensing database is backed up.
Back Up a Terminal Services License Server
http://technet.microsoft.com/en-us/library/cc753582(WS.10).aspx
Back Up a Terminal Services License Server
http://technet.microsoft.com/en-us/library/cc753582(WS.10).aspx
