I've had this problem ever since I got my simultaneous dual band Airport Extreme a few months ago. It will not connect to the internet unless I keep my old Belkin router between it and the cable modem. These things are supposed to be efforless, but I can't get the thing to work right. I start with the default settings, and no matter what I do, it will never connect to the internet unless I connect the WAN port on the APX through the old Belkin router whose WAN port goes directly to the cable modem. Is this a problem with the unit itself, or settings? Anyone else had to deal with this before? This thing was supposed to be my replacement, not another network add on.