I was having the same issue as everyone here - could not connect to my media center PC with my Xbox 360 - yet I could see the 360 on the network. I followed all of the instructions here and none worked for me. But they did get me looking and I was able to fix my issue. While in the "services" list (and mind you I'm on Windows 8 Pro retail) - I found the following service disabled: Media Center Extender Service - Disabled. I set it to "Automatic" and started it - and my problem is now gone. Works great. So I hope this helps others who may have this issue. Thanks to those before me for posting their fixes!