Problem Connecting to WPA2 Encrypted Wireless Network Wi-Fi in Windows XP SP2
For those who are not familiar with wireless security protocols, WPA 2 is an improvement over WPA protocol. It can offer increased security and will refuse access to computer users who do not know the authentification key set by the owner of the wireless router. Three are the options for wireless locking: WEP (Wired Equivalent Privacy) is the minimum security setting and is not advised anymore because it can easily be cracked, thus the authentification key can fall in wrong hands. WPA followed, offering way stronger security, but this too, with a fast computer (fast processor actually) and a big dictionary can be cracked, unless the key is strong and long enough. WPA 2 is considered even safer.
Computers running Windows XP with the Service Pack 2 have problems connecting to wireless routers that are secured using the WPA 2 (WiFi Protected Access) security protocol. This is because WPA 2 was not ready at the time Service Pack 2 was released, so such computer cannot identify correctly the security setting of a wireless router and cannot connect to it.
Actually there is a way to make systems identify the WPA2 wireless routers correctly, by installing a patch provided by Microsoft with Windows Update. Problem with that patch is that Microsoft decided not to include it in vital security fixes, so user will probably have to search much before locating the solution to his problem.
You can get this update by visiting this link and proceeding to validation, so Microsoft can make sure you are using a genuine Windows XP installation. After validation you can download KB893357 which is the actual update file. You can install it, restart the system and right after, Windows will recognize any WPA2 wireless router and will connect to it without further problems.
Attention is needed however for users with Windows that got different language, because they will need to install the update for the correct language version of Windows.