Re: External Hard drive issue.
Going to assume you're on Win7/8:
With the external plugged in, click Start -> type "disk management" (without quotes) -> Click "Create and format hard disk partitions"
Does it show the drive in the list at all? If so, what filesystem does it show? If it shows a filesystem (other than RAW)/recognizes there's a drive there, make sure it has a drive letter.
If it's not showing a drive, then I'd suggest burning a Linux LiveCD (such as Ubuntu), boot off of it with the drive plugged in, and see if Linux can recognize it.
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