I just recently made the switch from PC to MAC. In doing so I also purchased the airport extreme. I decided to see if my PC laptop would connect to the wireless airport. When doing so I get a message asking for a WPA Key. What the heck is it and how do I find it? Is it for the MAC Pro or for the Laptop? I'm obviously not very tech savvy, so any detailed help you can offer would be greatly appreciated. Thanks in advance