We have had several computers that were recently reloaded that had the Symantec Antivirus LiveUpdate grayed out or locked out.  This may be as a result of a group policy or policy pushed through the Symantec server, however, there is an easy fix for this.  To re-enable Symantec LiveUpdate using the following code and regedit.

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Intel\LANDesk\VirusProtect6\CurrentVersion\PatternManager]
"EnableAllUsers"=dword:00000001