Cant connect laptop running windows xp to cisco e4200v2 router

[Jules 49]

I am not able to connect a laptop running windows xp to my new Cisco E4200v2 router; no trouble connecting to laptop with Vista or to desktop running Windows 7...help

 

[Saga Lout]

Hello and welcome to Tom's Hardware Forums.

At what stage does connecting break down? Is it before or after the security key is input?