Media Center Service Turned Off

I am trying to get my XBox 360 to find my PC, or get my Windows Media Center PC to find my 360 as an extender.

For some reason every time Media Center searches(put in the 8 digit code on the PC) I get:

"Media Center Extender Setup failed as the Extender was detected on the network but the UPnP search for the Extender failed (timed out after 20000ms)."

in the event log.

It shuts off my "Media Player Extender" service(stops it and changes it to "disabled"), and unchecks the Windows Firewall box allowing Media Center Extenders through my home network.

I've tried disabling my router's firewall (Linksys WRT54GS) and Windows Firewall, then restarting the Media Center Service and still get the same message and results.

I've enabled uPnP, and disabled "filter multicast". I've tried messing with the Xbox's IP settings, but that wouldn't cause my PC to shut off the services.

I've done just about everything I can find on the internet to fix it and nothing has worked so far, have only seen a couple of threads talking about the service shutting off by itself.

I'm about to the point where I'm going to re-install Windows 7, but I haven't had it for very long at all so I doubt a "fresh" copy will make any difference. Read more at the forums...