Symantec Virus Definitions Not Updating

If Symantec is repeatedly popping up messages that the Virus Definitions are out of date, you may need to upgrade Symantec Endpoint Protection to the newest version, version 12 (as of 3/26/15). On a Mac you will not get the messages so you won’t know if the definitions are updating or not.

Knowledgebase article – Checking which Symantec Endpoint Protection version you have for both PCs and Macs.

Upgrade Symantec to version 12 from version 11, click this link which takes you to the ITS Symantec download site.
Then select either Site 1 or 2 and follow the prompts.