This is likely due to the router not being setup for DHCP. This would mean the IP address would not be assigned on the wireless device. This will either need to be enabled or have the wireless device setup for a static IP in the same range as the Router.
I have the same problem as the person who started this discussion. Cable modem, desktop PC, and laptop. I purchased a Belkin wireless router and wireless USB adaptor. Hooked it all up, worked fine for maybe an hour, with an occasional interruption here and there (had to sometimes click on links 3-4 times to get them to go). Anyway after about an hour it completely stopped working, both the wired desktop and my laptop. If it has to do with DHCP, how do I go about enabling the IP address/ assigned to the wireless device? Or the other? I am not real familiar with all of this, I just know basics.
Thanks for your help, this has been very frustrating as every time one of us needs the internet, we have to switch the cable from one computer to another...I just want to both be able to use the internet at the same time!