Networking XP

I have a small network with NT,9x clients with a 2000 server box. Try as i may i cant see the xp box on the network.I can browse the network from the NT Machine and the 9x machines but i cant from the xp box. I can ping the xp box from the server but cant ping the server from the xp box
I’ve checked the most obvious ie DNS etc Has anyone else out there encountered this problem. If so how did they overcome it