Is there something that could be blocking the signal or are you too far away? If the desktop works, and all you did was unplug it to move it there really isn't a good reason for it not to work. Make sure wireless is still enabled on the laptop. If it won't connect at all you can try hard coding the SSID (network name) into Windows XP. View Available Wireless networks/Change Advanced settings. Once you're in there you can clear out he memory of any other networks it's been on and see if that has anything to do with it. It would be good if you to limit this to the laptop or the router. Do you have any other wireless shit?