hi have external usb hdd but windows can't see it, it's old drive and was working, windows recognize drive serial model and it doesn't show in explorer, it's seagate and i tried to format patition with disc wizard for windows, i also tried partition magic and no luck do i have to format usb hdd in dos or i can do it with windows, device menager showes usb mass storage and everithing looks ok but no drive letter in my computer thank you