I have a Dell Dimensions 8200 Desktop(circa 2002) running Windows XP with
SP2.  I just bought a D-Link DWA-130 Wireless N USB Adapter and I am trying
to connect this set up to a Mac Airport Extreme wireless Router.  The PC
recognizes the wireless signal and correctly identifies the network.  
However, when I attempt to connect, the PC does not connect.  I have a
Toshiba laptop running Windows XP with SP2 that connected to the network
without incident the very first time and remains connected.  I have compared
the settings of the laptop and desktop and they are virtually the same --
Network authentification WPA2-PSK, etc.  The desktop doesn't seem to want to
accept the network key.  Why can't I get my desktop to connect???  Is there a
security setting that is to blame or an update issue?