Hi, the first thing to check is that the IP's are valid by "ping"ing them. Go to the DOS window, and type ping xxx.xxx.xxx.xxx and see if you get replies or timeouts. If you can ping one machine from another, then communication is possible. You might find that the machines are on different subnets, and this might cause you problems, or that the PC's are behind firewalls, which is blocking the port, as Mads said.
Hope that helps Sacha Emery National Instruments (UK)
