I networked my 2 PCs with a Linksys router and was able to share files between the 2. One PC has XP Home Edition, the other XP Professional. Later I installed Norton Internet Security 2005 on the PC with XP Pro, and could no longer access the 5 shared folders I set-up in the other PC. I disabled Norton Personal Firewall and was able to access the SharedDocs folder and the administrator's folder (the other 3 folders were still not accessible). After I re-enabled the Norton Personal Firewall , I was still able to access the same 2 folders and not the other 3 folders.