After upgrade if you import the license file or enter the serial number it says the license has expired and does activate the product. The default license shows different date each time you login (as 4/5/2555)
This license has reached its expiration date and is no longer valid.
SEPM not successfully upgraded.
1. Browse to C:\ Program Files\ Symantec\Symantec Endpoint Protection Manager\ bin (Default installation path)