The OS is XP sp2 I've tried all four of my usb they are all do the same thing. I've tried the card reader on another computer purchased about the same time and it finds the driver and works fine. So I got into device manager and look at what driver that computer used to make sure they are on my computer and they were, so I copied them and installed them on my computer but with no sucess. I've disable McAfee firewall and visus scan to see if that will work and it didn't. My USB ports do work for my printer, scanner, and my flash drive.