Pinging a machine on the network

[SLP]

Hello All,

I have a windows XP SP2 laptop with the firewall turned off on our network.
I log into the network with this machine and I am able to see the assigned
network drives and I am also able to ping any machine on the network. The
problem is I can't ping this machine from another machine either via the ip
address or the machine any ideas as to why and how to fix the problem?

Thanks