Pls assure the following
Name resolution between the Primary Symantec AntiVirus server and Symantec Endpoint Protection Manager (SEPM) works
The Remote Registry on the Primary Symantec AntiVirus server can be accessed from the Symantec Endpoint Protection Manager.
The C$ and Admin$ shares on the Primary Symantec AntiVirus server can be accessed from the Symantec Endpoint Protection Manager.