The basics for troubleshooting are:

1. Make sure you have the same IP scheme (e.g. 192.168.0.x).

2. Make sure you have the same Subnet Mask, Gateway, and DNS IP addresses.

3. Make sure you can ping the other computer's IP address. If this fails, just for testing, make sure you turn off XP's as well as any other firewall.

4. Make sure you can ping the other computers by name.

5. Make sure you have the same workgroup name (watch for trailing spaces)

6. For troubleshooting purposes, turn off XP's and completely uninstall any other firewall software. You can always add more complexity after you get it working.

7. With XP, make sure you have the same username and password as the person logging onto the other computers. The default setting for XP Pro is to require a password for network access.

8. More details about how to network XP can be found at: