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On January 5th, 2015, Symantec Endpoint Protection version 11.0.x will reach end of support life. Virus definitions and security updates will cease to be published to LiveUpdate and general support for the product will no longer be provided.
The initial end of support life date was originally scheduled for January 5th, 2014. All customers were provided a complimentary extention. No further extentions will be provided.
It's strongly recommended to upgrade to SEP 12.1 , RU5 is the latest release.
Best practices for upgrading to the latest version of Endpoint Protection 12.1
http://www.symantec.com/docs/TECH163700
FAQ: Upgrading Symantec Endpoint Protection 11.x to version 12.1.x
http://www.symantec.com/docs/TECH207274