3TB My Book Essential suddenly not recognized on iMac OS 10.6.8

I have two 3TB My Book Essentials. P/N WDBACW0030HBK-00 2911D. They worked fine on my IMac (Mac OS 10.6.8) for about a year but now neither one is recognized. I cannot see them in the desktop or in diskutility. One of them mounted briefly, said it had been improperly disconnect, but then disappeared and I cannot get it to reappear. The other one just disappeared one day and I cannot get it to reappear. The light comes on when powered up and plugged into the USB port on both of them.

I’ve searched all kinds of bboards, including this one and have seen similar, but not exactly the same problem. The thing that makes my situation unique is these used to work but now do not.

I downloaded the latest drivers today (turbo) but that made no difference. I cannot upgrade to the latest firmware because the disks are not recognized.

Thanks in advance

Hi, try running a test using Disk utility.

How to test a drive for defects or problems on a Mac

Hi!

Can’t use disk utility since disk doesn’t appear. Any other suggestions?

:smiley: