machinetech

Well, it could be a number of things, first, is the server you are trying to connect to a DNS server? Are you running Active Directory? What OS is on the server and the clients? Are you using WINS server? (older systems) On your client machines, you need to go into TCP\IP properties and set up your primary and secondary DNS servers and default gateway. They may be pointing to your ISP's IP address and that could cause the problem you are having. I am assuming that your machines are in a Domain. The possible reason you can connect using the IP address instead of the name is there is no DNS resolution. Need more info.