Wireless adaptor won't connect!!!

[evilsatan]

For the sake of simplicity I turned off securityo n the connection so I could add it later. Plugged the adaptor into the console, went into the settings, chose my internet connection and it says connected. But... When I go to test Xbox Live it always says failed at the IP Address stage!! I have searched Google but a lot of people have problems, I can't find this exact problem anywhere.

Any ideas? I tried to set static and enable DMZ on the router but no luck...

The setup is a router which stands alone, a computer with a access point and the 360 with the adaptor. Signal is not a problem as neither wireless device is more than 5 metres away from the router.

Cheers!!

EDIT:
Quite proud, fixed it myself!! Will leave this thread here in case it helps anyone else, basically the router is set to use PPPoA and the settings in the Xbox were asking for PPPoE, my eyes didn't notice they were diff letters (doh!) so I entered the routers PPPoA settings in! So simply cleared them, added security, now connected A-OK!.