After upgrading Symantec Endpoint Protection (SEP) client between (14.0 RU1 - 14.2) builds, the server periodically goes into a hung state.
Windows Server 2008 R2
Windows Server 2012 Server
This was a race condition while trying to call a ReferenceObject that was deleted in PreCleanup at the time we were trying to acquire oplock file object.
This issue is fixed in Symantec Endpoint Protection Client 14.2 MP1. For information on how to obtain the latest build of Symantec Endpoint Protection, read
TECH 103088: Download the latest version of Symantec Endpoint Protection