Windows 7: Xbox 360 Extender set up

I can't seem to get the Media center to set up my 360 as an extender. Keeps telling me there is an error. The Xbox is being picked up by my computer but as soon as I enter the set up key the error comes up. I have done everything I've read so far and nothing works. When I go into services and try to turn on the Media Center Extender Service it keeps going back to disabled.

Any help would be great.

Check your router/firewall for permission/specific updates.