Network access

[Kristen]

I have a small home network set up with two computers.
One is a PC running windows ME and the other is a Laptop
running windows XP. The Laptop has a wireless adapter
and the PC is connected to a router. Both computers can
access the internet and both computers show up in My
Entire Network. I can access the XP(Laptop) from the ME
(PC)but I cannot access the ME(PC) from the XP
(Laptop). Every time I click on the ME(PC)icon in my
network
I get this message

//Comp1 is not accessible. You might not have
permission to use this network resources. Contact the
Administrator of this server to find out if you have
access permission. THE NETWORK PATH WAS NOT FOUND.

Can anyone help with this problem?