I have two computers, one windows vista home edition connected to internet, another one Windows Xp stand alone. With 5-port 10/100 switch connected to them. The two computers connected as workgroup and share files and folders in both, yet cannot see the computers communicating to each other. Any idea what I have to do?

Larry,

Help me out here, please, exactly what do you think you should be seeing?

I'm going to take a wild guess here and try to describe the topology of your lan.

One DSL modem/router with four data entry ports and one phone line connection.

Both computers share the router to "talk" to each other. The router splits access to the internet between the computers. There is never a guarantee of "Instant" accesss. The router code is polling each data entry point to see if it has data to transmit to the Internet.

If you are expecting to see traffic between the two PCs, you won't, unless you want to spend about $2K for a decent quality network sniffer to read all the traffic on your network.