GaZZuM

Same problem here, and the suggestion above unfortunately did not work, here's what happens. I got the 8-digit code off my 360 and wrote it down, i went onto media center and attempted to add an extender and get stopped at the same point as above, telling me to enable UPnP, make sure Xbox 360 is turned on and connected to network and make sure that that the setup key is correct, all of which I have done. As above my Xbox 360 shows up in my network map as part of the same private network as my PC. What is probably different about my setup is how my Xbox gets online... Basically it goes like this: broadband modem connected to wireless router via ethernet, pc connected to wireless router via ethernet and Xbox 360 connected to wireless router via ethernet. The Xbox is much too far away to connect to the PC directly, and even if it did it only has one ethernet port so I wouldn't be able to go online with either device. What annoys me is that even with everything filtering through this one wireless router via ethernet cables my PC is taunting me by including the Xbox 360 in the network map... why would it do that if I couldn't connect to it?!?