Have you tried changing which USB port it's hooked into. If not is there any cd (Drivers/Software) for your external / that it came with? If not you might have to search for unrecognized hard ware. This will help with that: http://www.techmantras.com/content/finding-drivers-unrecognized-hardware-windows-system
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Have you tried changing which USB port it's hooked into. If not is there any cd (Drivers/Software) for your external / that it came with?
If not you might have to search for unrecognized hard ware. This will help with that: http://www.techmantras.com/content/finding-drivers-unrecognized-hardware-windows-system