We are running in multiple vlan environment over a 6513-Sup720 environment. Our server guru's are complaining that RPC connections initiated from our server vlan cannot communicate with our user vlans. RPC connections initiated from our user vlans to the server vlan are successful. If the server is temporarily moved to the user vlan, we get successful bidirectional RPC connectivity from the server to the user and vice versa. We're running in a Microsoft server environment. About 4 months ago this problem went away after Microsoft recommended some form of server patch. Recently it came back after a server upgrade. The previous server patch does not fix the problem this time. Our server guys are blaming the network.