File sharing problem after replacing router

Hi there, I have 3 PCs in my home network: 2 running XP and 1 running Vista. I had a 80211g network using a wireless router. A few days ago I upgraded the network to 80211n, by replacing the wireless router (to Edimax BR 6524n) and NICs (to Edimax EW7718). I now have internet access working fine, but cannot access one PC from another. Ping is working fine, and after I have run the Windows home network wizard to reinstall file and printer sharing, I can even see the other PCs in the "My Network Places" window, but when I click on one of them - I get an error that I don't have permission to continue. So it looks like the TCP/IP works fine, but Windows file sharing has a problem. I really hope you can help me with this. The main reason I upgraded to the faster network was because I am copying big files from one PC to another. Thanks, Yuval.

Create a "user account" on all three computers that is the same and with the same login password. You "may" not be able to access the networked computers from each other, because you must able to log in.