Xbox and Windows Media Center

Hey guys,
im having quite a bit of trouble with using WMC on my xbox. I previously had it set up and working fine, but then one day, WMC on the xbox could not find my computer. I have been attempting to set up the connection again but my computer says it 'cannot set up extender'. The online help is not very useful.

I do not think it is a problem with my router (2WIRE Uverse), because when i test the WMC connection on the Xbox, it connects to the network fine, but has troubles communicating with my PC. Both the xbox and Pc are wired and i have no anti virus software installed.

I have tried factory resetting my router, messing with firewall and DMZ settings on it as well. Also, i have completely disabled both the private and public firewalls in windows...no dice. Im running Win7 Ultimate 64bit. Id love to try any suggestions you may have.
Thanks in advance.

did you change any media sharing options? also what is your OS?

Not that i know of. Im running win7 ultimate 64bit

This is very confusing. Everything seems perfectly fine.
Not 5 minutes ago i was able to set up a new WMC connection on my netbook just to test.
Ill keep troubleshooting...