I have a few problems with this Client server network that has me really puzzled. This network has a DNS server that is used as a application server. It is running server 2003. There is a cable modem that is connect to a router that supplies the DHCP. Who ever set them up has the DHCP running on the router at let say 192.168.0.1 IP address, and the DNS at 192.168.0.5. The problem that continuely comes up is one or more computers will lose site of the server. I still pulls a valid IP address, but is not able to acces the server. The internet comes in through the cable modem to the router into a switch. The server is only connected to the switch with one cable. If that helps.