I have connected by 500g WD usb drive to my computer, it sees the drive and I transfered 200g worth of files to it. The internal drive is formatted NTSC and the external is Fat32. When I go to reboot the computer it freezes at the bios page. If I unplug the external drive and reboot all is well. When I plug the external drive in once the computer is running it is detected and all is well. How can I solve this problem.