I created a homegroup on a W7 RTM machine that I was using for testing. Didnt bother to write down the password because I wasn't planning on using it on another machine at the time. Later I installed a new W7 RTM over the test version. When I try to join a homegroup it wants the password for the machine which no longer exists? It won't allow me to do anything else until I give it that password. I tried shutting down all the PC's, router, etc for a while but no luck. Is there a reg hack or something I am going to have to do to get rid of the phantom PC?