So today my xbox 360 returned to me and guess what? It’s a replacement. The tell tail sign was a new MAC address :-|
So I have hooked it up to my TV and the network and applied the update. Configured my Vista Media Centre to work with it and worked first time (unlike my old 360!)
So I wonder what was wrong will my old 360 … I guess we will never know if the two updates broke it?!