Using a Dell Optiplex GX270(WinXP Pro), and my USB flash drives(I've tried a few) cannot be recognized in My Computer. I tried the front and back USB ports, and no recognition. My Zip(250) and scanner(canon) and Laserjet(HP) all work off the USB drives but not the flash. I went and removed the upperfilters and lowerfilters in the registry, and the USB problem still persists. Any suggestions? Many thanks!!!!