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You can only upgrade to Windows 10 Anniversary Update with Symantec Endpoint Protection 12.1 RU6 MP5 installed. You must uninstall or upgrade earlier versions of Symantec Endpoint Protection prior to the Operating System upgrade. The Operating System upgrade will stop if it detects an earlier version of Symantec Endpoint Protection.
Symantec Endpoint Protection 12.1 RU6 MP5 provides basic compatibility for Windows 10 Anniversary Update / Windows 10 Feature Update 1607.
Full support is planned for the next major release of Symantec Endpoint Protection.
Go through the following latest tech note:
Symantec Endpoint Protection 12.1 RU6 MP5 offers basic compatibility with Win 10 Anniversary Update.
Reference:">http://www.symantec.com/docs/TECH235458">Reference: http://www.symantec.com/docs/TECH235458