When you right-click on My Computer / Properties / Network Identification / Properties and try to join a Windows NT domain, you receive:
<b>The following error occurred validating the name "domain name".

The specified domain either does not exist or could not be contacted.</b>
If you NET VIEW, you receive:
<b>System error 53 has occurred.

The network path was not found.</b>
When you try to ping by name, it fails, but pinging by IP address is successful.

If your only protocol is TCP/IP and you disabled NetBIOS over TCP/IP, that is probably your problem.

This can also be caused by some 3rd party DNS servers, that do not support SRV records.

To enable NetBIOS over TCP/IP:

1. Start / Settings / Network and Dial-up Connections.

2. Right-click Local Area Connection and press Properties.

3. Select Internet Protocol (TCP/IP) and press Properties / Adsvanced / Wins.

4. Click Enable NetBIOS over TCP/IP.

5. Press OK until you are out. You can ignore the 'empty primary WINS address' message.

If you don't want to enable NetBIOS over TCP/IP, you could install NetBEUI on the clients and the server.