Bretto,
1. Check your network settings: IP Address, DNS Server, Subnet Mask, WINS
2. If these are correct, 'start', 'run', type command
3. At the dos prompt, type ping 10.100.25.4(using ip address of your computer), then press enter. If you get a reply, then the network card is fine.
4. Next "ping (ip address)" of a workstation on the network. If you cannot ping any of the other IP addreses on the network, you may have a cable problem. Try changing the cable.
5. Even if you assign the same IP address or name from another computer to your comupter, the network will recognize it and send an error message.
6. If you assigned the computer to the domain correctly, a window would've popped up saying Welcome to the domain XXXXXX