need help networking 2 2k machines

I'm trying to help my father network his 2 PC's, one of which used to be my sisters, so we had to reformat, and now they can't see each other or network drives. I tried searching the tips and tricks and past posts but couldn't find a post pertinent to my situation.

So here's the setup:

2 fully patched machines running win2kSP4
PC1 (his PC with the files that need to be accessed by pc2)
and PC2 (fresh Win2kSP4 installation)

PC1 has the files that need to be mapped to PC2's network drive.

PC1 can ping PC2, but not vice versa. Both are supposedly in the same workgroup, but cannot see each other.

PC2 can use the internet via a router.

Any suggestions?

 

Log to this page it has a lot of links to instructions to Windows Network Settings, and Sharing.

Link to: Windows Network - Installing & Sharing.