You would like to change the number of days before Symantec Endpoint Protection (SEP) alerts clients that virus definitions are out of date.
Release : 14.x
SEP uses the Windows Security Center to notify users that their virus definitions are out of date. The default is to notify when definitions are 7 days out of date.
These settings can be adjusted in the Virus and Spyware Protection policy under Advanced Options>Miscellaneous
To disable these notifications, set 'Display antivirus alerts within Windows Security Center:' to 'Disable'.
To adjust the number of days for which the user will be notified of outdated definitions, ensure alerts are set to 'Enable' and adjust the number of days in the 'Warn after:' box: