Are you using SEPM 11.x
You can upgrade your SEPM 11.x to SEPM 12.1.5
On January 5th, 2015, Symantec Endpoint Protection 11.0.x and Symantec Endpoint Protection Small Business Edition 12.0 will reach End-of-Support-Life and no longer be entitled to support, LiveUpdate, virus definitions and security updates. To remain protected, ensure all of your endpoints have been migrated to version 12.1 and activate the advanced protection available through Insight reputation scoring and SONAR behavioral monitoring. Endpoints that continue to run Endpoint Protection 11.x and SBE 12.0 after End-of-Support Life (EOSL) will no longer receive virus definitions, content updates, break fixes, patches, workarounds or technical support.
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Check these article
Upgrade or migrate to Symantec Endpoint Protection 12.1.5
http://www.symantec.com/docs/TECH224034
See Chetan upgrade articles
Upgrade Overview to SEP 12.1 Release Update 5 (12.1.5337.5000)
https://www-secure.symantec.com/connect/articles/upgrade-overview-sep-121-release-update-5-12153375000