I have two PCs, both connected to a Comcast modem/router combo unit via CAT5, both running Windows 7 Home Premium. Let's call them "Desk" and "TV", which is being used as a media center. I have tried everything I could find here and everything Mr. Google could suggest but Desk is denied connection to the Homegroup established by TV. So I thought I would start over, killed the Homegroup on TV, and selected to "Create a Homegroup" on Desk. But Desk says "Windows cannot set up a Homegroup on this computer." Windows 7 Home Premium is supposed to be able to do that, and it will on TV. So I think my first problem to overcome is simply getting Desk to be enabled to set up a Homegroup. If it could create one, I assume it could join one.