OMG Windows Media Player Media Sharing!

I have windows media player 11 and I'm reading a tutorial on how to stream WMP11 content to my xbox 360 and it tells me how simple it is. Click the arrow below the library tab go to more options and click the Configure Sharing box. But the thing that is seriously pissing me right off, since I cannot find support anywhere on it, is that the box is greyed out. I made sure all dependencies were on, made sure file sharing was enabled, restarted it and still on my screen greyed out. Whats going on?

 

I know that my computer can share, if I install Twonky my computer shows up righht away and I'm able to share everything. I just want to stream .avi from my computer to my xbox without a bulky media server

 

Firewall? Temporarily disabling firewall to see if that is the problem.

Could also be that you need SSDP Discovery Service and Universal Plug and Play Device Host Services running.