The Symantec Endpoint Protection (SEP) 11.0.6300.803 client downloads the Gup List from the SEPM. Although the file downloads successfully (HTTP status code 200), the client displays an error in the Sylink log which says "CheckSum do not match!"
As a result, the SEP client does not update definitions.
The following error was captured in Sylink logging:
<mfn_MakeGetGupListUrl:>Request is: action=320&hostid=839D8714xxx...
<mfn_DoGetGupList200>Content Lenght => 452
<mfn_DoGetGupList200>Got Gup List from server, read bytes=452
<mfn_DoGetGupList200> CheckSum do not match!
<GetGupList:>RECEIVE STAGE COMPLETED
The Gup List on the SEPM has become corrupted.
Recreate the Gup List using the following steps: