A user recently clicked the network diagnostic feature on his Windows XP laptop when hen could not remember the SSID password on a home Wi-Fi router (the usual NetGear type). The Wi-Fi will now correctly recognize the network ID from the Tasktray, but will not actually connect to the router after entering the Wi-Fi password. The wireless networks panel just reads "Automatic" instead of "Connected." Several other computers in the house connect wirelessly, and the laptop in question connects to the Internet normally by means of a wired connection.
I have tried disabling the Windows Firewall, to no avail. I have also verified that the Wireless Zero Configuration services is running.