File mysteriously disappeared but WinDlg reports all good


I had a file mysteriously disappear from my 2 TB Green drive. In the past I always saw that as the sign the drive was dying. First I ran some tests (I believe it was TestDisk), and the hard drive seemed to have died. I was wondering if it could be the case, so I tested it with another and it behaved poorly as well. Running more software it seemed hopeless, until I reset the usb hard drive case and restarted my computer. After that, I managed to copy all of the files and run a variety of tests including every test Data Lifeguard has. They all passed fine. I copied the files back on to the Green drive and have been using it off and on for a few weeks now with no problems.

What could the problem be? 

WD Data Lifeguard Diagnostics was designed to be used with the hard drive directly attached into the Motherboard in order to minimize inconsistencies with the analysis that may result from an external enclosure changing or affecting the results. I would recommend a second test with no enclosure, and then replacing the disk drive if it fails.