External Drive No Longer Visible

I have a external hard drive, which is a Western Digital 1TB SATA, in a external adapter. I usually hook it up to my laptop via e-SATA. Today I hooked it up, and the computer saw it just fine. I could access it, but not do anything with it's contents. Whenever I tried to play a video off it, WMP would say it could not play the file. Whenever I tried to copy a file from the external drive to my C: drive, it would give an error message, something along the lines of the file path no longer existing. So I unplugged the external drive, shut it off, and rebooted the computer. Now when I attach the drive, nothing shows up. Under Computer Management,the drive is not visible, even after a re-scan.

I can hear the drive making it's usual start up sounds when powered on, so I think the drive is OK. With the drive on, when I connect the SATA cable, the LED briefly flashes, and the drive makes a quick accessing sound like normal, but then nothing happens. It usually does that, then it'll continue to access, Win 7 will see it, and then I'm able to access it, but not anymore! The external adapter has a USB connection as well, which I tried, but that's a no-go as well. Win 7 sees my USB thumb drives no problem.

Any ideas? Is this a software issue? Perhaps my external adapter quit on me?

My primary C: drive, and my DVD/CD-ROM drive.

Hmmmmm....strange. I tried the USB connection again, and it worked! I think this may be an issue with either the e-SATA cable, or the adapter is having issues. USB is so much slower, but hey, at least it works!

Hello there novaks47,

I am really sorry for the issues you are facing with your Western Digital external hard drive. In my opinion this could be both hardware and/or software issue.
Have you done some disk testing? If not I would suggest you first start the troubleshooting by running the Data Lifeguard Diagnostic in order to see whether it can detect some problems with the disk (link below).
After the hard drive worked fine for some time and is accessible when you use USB connection I would suggest that the problem might be related to the e-SATA cable. If this is the case, you can try the following steps:

You can try a different e-SATA cable and adapter.
You may want to try the drive on another PC.

If the previous steps did not solve the issue, you may try to uninstall the drive and plug it in again in order to download drivers again.

Here is a link to the Data Lifeguard Diagnostic WD Support / Downloads / Other Products / Data Lifeguard Diagnostic for Windows

Let me know how it goes.
D_Know_WD