Originally posted by techs
What OS are you using? Do you have a network pcmcia card or built in network port on your laptop? Have you tried it connected to the Linksys router directly? Have you tried pushing the reset button on the back of the Linksys router while the router is on(this resolved a problem for me that merely unplugging and replugging in the router didn't)?
Re-read his post and you'll answer some of your questions.

Is WEP enabled on the AP? If so try disabiling and see if the lappie talks with the AP.