windows was unable to find a certificate to connect to this network

My laptop connects to the home wireless network successfully but a pop-up appears at the
system tray with the above title (windows xp). The problem here is because I had enabled
IEEE 802.1x but did not have a 802.1x (EAP) environment. The solution is very simple.
Select the corresponding wireless network in the laptop and on properties->authentication tab
disable this authentication. works like a charm!