Did you do an upgrade or clean install?
I did an upgrade and had the same problem as you. After doing a lot of diagnostics, it said that I had two services running NAT at the same time and that could be causing the problem. I had Microsoft OneCare installed which said it was not compatible with Win7 so I decided to uninstall that and now everything works fine and everybody can see everybody.
If anyone is having a problem with netwoking and you have Microsoft OneCare installed, don't just stop it running, but instead uninstall the whole thing and see if that helps. After hours of agrivation, that finally worked for me.
Did you do an upgrade or clean install?
I did an upgrade and had the same problem as you. After doing a lot of diagnostics, it said that I had two services running NAT at the same time and that could be causing the problem. I had Microsoft OneCare installed which said it was not compatible with Win7 so I decided to uninstall that and now everything works fine and everybody can see everybody.
If anyone is having a problem with netwoking and you have Microsoft OneCare installed, don't just stop it running, but instead uninstall the whole thing and see if that helps. After hours of agrivation, that finally worked for me.