My desktop's motherboard has a built-in wireless adapter. It connects to the wireless network fine (the same one that my netbook is using right now to post this) but it won't actually access the internet.
It does work when hardwired, but I need that hardwire for my 360, and I only have one jack from the house's router in my room.
Any help would be appreciated... I only know so much about networking.
Have you checked the IP's to see if there is a conflict?