Networking issues

Hello all, I need some assistance in setting up a peer-to-peer network using windows XP pro & home. I have three computers setup on the network, one running XP Pro & the other two running XP Home. From the machine running XP Pro, I can view all the files on the other computers on the network running XP home, but when I tried viewing the files on the XP pro machine from the XP home computer, I get an error message. The message reads something related to not having access privledges and to seek my system administrator. Can anyone shed some light on this issue……thanx