I had no problem with networking my new Win7 64 bit and my son’s Vista 64 bit.
I don’t know enough about networking to know When I’ve screwed something up.
I suspect that when I disconnected the XP 32BIT computer that was the wired access point and connected the windoze seven up to become the access point .. I screwed something up.
My Vista is on an adapter and That is the one that was giving me the problem.