When you use a UNC path to connect to a computer running an earlier operating system, you receive either of the following:
The remote computer is not available.
System error 53 has occurred. The network path was not found.
If NetBIOS over TCP/IP is disabled, you will experience this problem.
Windows 2000 uses the Server Message Block (SMB) protocol, used for file and printer sharing, directly over TCP, without using NetBIOS. Since earlier operating systems do NOT support this abilty, NetBIOS over TCP/IP must be enabled to communicate with them.
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.
4. Press Advanced.
5. Select the WINS tab.
6. Check Enable NetBIOS over TCP/IP.