When a single computer tries to connect to a terminal server session or a Citrix application you receive the message “The remote session was disconnected because there are no Terminal Server License Servers available to provide a license. Please contact the server Administrator”;
In my case this message was generated on a laptop after the hard drive had been moved to a replacement laptop.
The users cached terminal server license may have become corrupt, the below goes though how to delete the machines license;
1) On the effected computer open Start => Run => regedit
2) Expand HKEY_LOCAL_MACHINE\Software\Microsoft\MSLicensing\Store\
3) Delete the license key LICENSExxx under the store key