The Globally Unique ID (GUID) specified by this computer is not valid

The GUID reported by this client computer is invalid.
Your computer reported to the server that its GUID was

     %GUID%

You can check the GUID that is normally found within the computer's BIOS configuration settings to verify that it matches the GUID listed above. If it does not match, restart your computer.
If the problem persists, contact your network administrator for further assistance.