I take such a drive and plug it into another machine. If it fails there then the drive does have a defect. Such drives are not "backup" or worthy to carry our one copy of any files and must be "backed up" just like our other hard disks.
I'll not write about the recovery methods since that discussion is on this page.
Bob
Hello,
I am having problems with a SimpleTech 250G external HD. Things were working fine, until suddenly it became very sluggish. I have a lot of music on the drive, and it got slow to the point that songs were skipping and not playing properly. From there, i stopped all eHD drive activity, but my computer still acted very slowly, and the eHD kept making noise.
I let it go for a while, not having time to deal with it, and not knowing where to start. But, the problem came up the other day when i needed to access some of the files on it (and i really wanted to listen to some of the music too), and it would not load.
I plugged it in, turned it on, and my computer slowed way down, but acted as though it recognized the drive. Problem was that it took forever to show up in My Computer -- And when it showed up, it never worked worked. Several times I would click on it, but eventually i would receive an error that
''I:\ is not accessible. Error performing inpage operation.''
With a quick Google search, i found out that Microsoft says this is often a physical problem, which is really not exciting.
Either way, if anyone has any ideas or recommendations, I'd be really grateful -- and let me know if you need more information. Thanks for your time!

Chowhound
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