Hello,
Are the SAV 10 .x Clients Managed? Are these Updating from SSC?
What about the SEP 11.x clients, Are these Managed and Receiving updates from SEPM?
Are you running any Proxy on the Server?
If yes, then please try updating the SSC and SEPM with the Latest Updates and check -
Updating virus definitions for Symantec AntiVirus Corporate Edition 10.x and Symantec Client Security 3.x
http://www.symantec.com/docs/TECH101198
How to update definitions for Symantec Endpoint Protection Manager (SEPM) using a .jdb file
Article: TECH102607 | Created: 2007-01-08 | Updated: 2012-05-01 | Article URLhttp://www.symantec.com/docs/TECH102607
A Quick Update for the SAV 10.x, it's Time to Migrate, check the Article below:
Be Aware: The Symantec Antivirus Corporate Edition 10.x and Symantec Client Security 3.x End of Support life is fast approaching!
https://www-secure.symantec.com/connect/forums/symantec-antivirus-10x-sav-will-reach-end-support-life-eosl-4-july-2012
Scan Engine Version information is unavailable in Symantec AntiVirus 10.x as viewed in the Product GUI or Symantec System Center
http://www.symantec.com/docs/TECH189026
Hope that helps!!