Symantec Endpoint Protection Manager (SEPM) 11 is not updating the virus definitions for Symantec Endpoint Protection (SEP) clients. SEPM shows old virus definitions in Admin > Server > Local Site > Show LiveUpdate Downloads.
There are a couple of possible causes
There is no more space available in the database used by SEPM.
Old or corrupted virus definitions prevent SEPM from updating clients with new virus definitions.