I have two computers both running Windows 7 Ultimate. They were communicating with each other flawlessly and I could transfer files between them with no problems. I use one for a backup of the other. Suddenly without any changes to them, the transfer rate dropped drastically. It would have taken over 4 hours to transfer 700meg of data. I use one for a backup of the other. Thinking it might have been a problem with the old Linksys WRT54G router, I purchased a ZyXEL GS105B switch. I have both computers connected to the switch and then from the switch to the router and from the router to the DSL modem. Both computers can connect to the internet and also to a networked printer with no problem. They just cannot connect to each other. The Linksys is running the latest Tomato update and I think this is where the problem is. Is there something Im missing or need to setup?