External Hard Drive Trouble

I have an external USB hard drive that fails to mount on the desktop. What happened was I apparently had it plugged into a switched outlet, and then when someone flicked the switch it lost power before it was able to be safely ejected. Now when it's plugged in and booted up, all goes well as usual in terms of the sounds it makes and the connections, but my macbook never recognizes it. It doesn't appear on the desktop or in disk utility.

I tried using the application called DiskWarrior, and it doesn't see the drive either, even when booted from the disk. I even took the drive out of its enclosure and put it into a PowerMac G5 tower and ran DiskWarrior on that computer and had no luck again. Does anyone have any suggestions on how to get a computer to recognize the drive? Even if I can't salvage my files I'd like to be able to at least reformat and be able to use the drive again, but every computer seems to ignore it.

I find it hard to believe that simply losing power can cause a fairly new hard drive to fail entirely, especially because it still sounds normal, no clicks or any other strange sounds. But then again, I know nothing about the technology of the hardware. Thank you so much in advance for any advice anyone has...

When my wife shutdown her iMac mid back up and the Ext HD would no longer mount, i opened up the HD enclosure removed the multi pin plug but left power plug in and powered on for 7 or secs then shut down reassemble and it mounted on desktop. That was for Firewire i assume it would be same for USB.

I'll give it a shot, thanks for the suggestion.

No luck. I've read that leaving it unplugged for a while and then trying can help? So I'm going to try that for now...

Yes, leave it unplugged completely, overnight for example, see how that affects things.

There's more to suggest, so keep us posted.

Thanks so much, I'll leave it unplugged tonight.

So, I left it unplugged from the wall for over 12 hours, and when I just tried to boot it up again, no luck. The drive spins up, but never shows on the desktop. Anyone have any suggestions? Thanks...

Your external hard drive probably suffered "brain damage" when its blood supply was cut off. (AC power) Who makes the hard drive and is it still under warranty? If it's still under warranty, get an RMA from the manufacturer and send it in for a replacement.

Regards.

Because, as you point out, the drive spins and appears to be doing its regular 'thing', it may in fact be the controlling chip (Prolific, Oxford?) in the enclosure, that's suffered damage.

Take the hard drive out of the enclosure and try connecting it to your Mac with a USB/ATA/SATA adaptor, like this Newer Technology Universal Drive Adapter -... (U2NV2SPATA) at OWC. There are other brand adaptors from other sources as well.

If you don't wish to buy one of those, then, as advised, take the drive to a Mac tech for assessment/repair/replacement as appropriate.