[gavvys]

Hi
First make sure the basic settings are fine because if you are able to ping one machine then that machine should also be able to ping.
Make sure gateway settings are fine,
check the ARP entries in the machine whether it is taking the right ARP entry or not,
while pinging check the logs in the firewall, whether you are getting any logs or not,
also check the windows XP firewall settings.

If it again doesn't work then let me know the network architecture, I mean a bit information about your network, that will help in resolving the issue.


I hope this will help you.
Regards
Ranjit