XP-98 Networking (URGENT)

In case of emergency, I turn to you guys :D

My mate just brought his PC round, and we networked his (running XP updated from Win98) to mine (Win98), so he could copy some stuff to my HD before formatting his.
I enabled File Sharing etc. and everything worked fine, but once we finally got XP set up on his HD (clean install), it couldn't access my PC. Once twiddling a couple things, he could successfully ping the hub and my PC. But when opening "My Network Places", there are no files, where there were before.
He wants his files back, but I can't work out what is wrong. His notwork card is installed properly, he can ping to the PCs by IP, and we are members of the same Workgroup (WORKGROUP).

Any ideas?











yes I know XP's ****. He just likes it. ok