My mac has been having problems seeing other pc's on my netowrk,but my pc's can see and access mac folders.I have all my pc's(2 xp,1 vista) with sharing enabled and password sharing disabled and its set up to the proper domain name.The mac can connect to the internet and it passes network diagnostic test .Mac has file and printing sharing enabled.In the past when I would reboot the mac,after a period of time all the pc's would show up under places.Need help