Thanks for the suggestions.

Here's the latest update: I still have my old desktop computer running Windows XP, so I decided to plug the drive into it to see what would happen. (I switched to a Windows 7, 64 bit laptop back in 2011.) The other difference is that I use a firewire connection to my desktop, but a USB 2 to connect to the laptop.

Everything seems to work fine! I was able to copy some large files from the drive to another external backup drive without any problems. I ran chkdsk and it ran at normal speed, though a tad slow since my desktop computer is slower.

Now I'm suspecting there's something wrong with the USB port on the hard drive. It's odd that I've been using it for a few years, but it's only started making noises yesterday.

But, I'll try running a defrag and then plugging it back into my laptop to see what happenes. Luckily, my backup drive has enough space if I need to copy the files to it.

And what's the difference between the chkdsk in the link you posted and Windows' chkdsk?

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