I have a XP-Pro desktop and two XP-Home laptops that wander about the house. The laptops are wireless to a D-Link AP/Router only, no networking between any computers. It took about two hours at least to figure out WPA versus WPA-PSK. Got a "where's the certificate" on WPA originally but after you wander through all the new options it's all there. I settled on WPA-PSK only because it's easier for me to understand when setting up. It use to take about a minute for the laptops to grab on to the AP and now it's there in a couple of seconds. Works great!