Vista - ICS not working? +REP

Okay, I need to use ICS for Xbox Live access.
I started of fine, but then all of a sudden - it stopped working!

I now try to use the same method (ICS on Local Area Connection(Wwhich is the ethernet cable from my xbox 360 to the computer)), and it comes up with the message;

IP Address Conflict.
There are more than 1 computers using this IP Address.

I then try network bridging, but I cannot access xbox live...

I've tried resetting my router, and tried reformatting my computer.
No clue why it won't work, but do any of you?

+Rep to all helpers

Try restoring the Xbox to factory settings.