Network timeouts or packet drops with VMware tools 11.x installed and the Symantec Endpoint Protection (SEP) client. Other symptoms include Nslookup or Ping failures.
This is not a Symantec Endpoint Protection issue. This issue is documented and fixed with VMware Tools 11.2.6 or newer.
Please see the following VMware KB: Network timeouts or packet drops with VMware Tools 11.x with Guest Introspection Driver (79185) for more details.