For connection issues with an external hard drive, I would suggest starting your troubleshooting by resetting the parameter RAM. See this article for a description of how -
Note that the article says it is for Macs running OS X 10.9 (Mavericks) but the procedure is the same for earlier versions.
If that does not resolve the issue, look in your System Profiler (go to the Apple menu > About this Mac > System Profiler and look under Hardware in either USB or FireWire depending on how the hard drive is attached. Does it appear here? You may have to use the disclosure triangles to expand the connections. See this article -
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Unfortunately to no avail. I did the PRAM reset twice and then opened my system information. It doesn't appear to be registering the device at all.
Under USB I can see:
USB Bus > BRCM2046 > Bluetooth USB host controller
> IR Receiver
> Apple international keyboard/trackpad
USB Hi-Speed Bus > Built in iSight
USB Hi-Speed Bus > internal memory card reader
And under FireWire it lists only Maximum speed: up to 800 mb/sec.
Unfortunately the two options you suggested seemed not to work.
Any other suggestions?
Thank you for your help,