Click on Properties once you select the wireless network that is having problems.
Click on the Authentication tab and now uncheck the Enable IEEE 802.1x authentication for this network box.
In this window make sure you are in the "Association" tab.
Here’s how to connect to your wireless router if you are getting this message.Select your encryption type from the "Network Authentication" and "Data Encryption" drop downs.Uncheck "The key is provided for me automatically" and enter and confirm your Network key.This article also describes the most common problems with IAS authentication and authorization, certificate properties, and the process of certificate validation for both wireless client and IAS server certificates.This article assumes background knowledge in IEEE 802.11 wireless LAN and associated security technologies and the components of a Windows-based authentication infrastructure.I have unchecked the authentication box in network properties and entered the existing network key. steve UPDATE: My home net was set to WPA2 (from my Win7 desktop), which XP doesn't appear to offer. The IE error apparently is due to an old version, I switched to Firefox and there are no further problems.