If you have installed the Atheros Wireless Client to fix the no wireless networks we found in range problem with windows XP, an atheros wifi card and a toshiba laptop then you will need to configure the client if WZC - Windows Zero Configuration still fails to function correctly.
Open the client by clicking the new icon by the clock to display this screen:
Click Scan and select your SSID, select the type of encryption and the size of the key (for WEP)
Paste in your KEY (or type it in) and save. Suddenly the wireless should be obtaining an IP from your router and you will be back online in no time.