I have a Western Digital My Passport Essential SE 750gb USB external drive, which has been chugging along quite happily for the last year and a bit.

A few days ago I upgraded both my iMac and Macbook to 10.7.3 and now the drive won't mount. It powers up and makes all the normal noises, but simply isn't recognised by the system.

Google tells me that 50% of the people are having an issue with 10.7.3 and drivers, and the rest have a defective drive. In my case I'm leaning more towards the former as it's happened around the same time as I installed the OS update. However, I've installed the drivers from the WD site and still no luck.

So, my question is has anyone else experienced this or able to offer a suggestion? TIA.

Originally Posted by Biallystock

Obvious thing to do is put it on a Snow Leopard system and see if it mounts.

To isolate problems you have to have a divide and rule approach. No point guessing when you can simply test.

It never ceases to amaze me how trusting people are on upgrades. I never let any OS takeover my Macs until I am satisfied they are safe and work as advertised. New OSes always start off on external test hard drives on all my Macs. If they pass muster, then they get installed on the internal drive.

Don't really have access to a Snow Leopard system right now. I'll check the TAFE computers tomorrow though.

You're right on the upgrades, but to be fair, it's reasonable to think that something as simple as a USB drive would be unaffected with what's only an incremental OS upgrade.

Originally Posted by jusrus

Am I right in saying that drives don't appear on the desktop as per earlier versions of OSX in Lion? Have you checked the bottom left hand part of a Finder window?

I have. It powers up ok, just not being recognised at all.

Tried today on a windows machine and same thing - powers up but no other response. Looks like it's a dead drive. Regardless, I'll see what I can do to get it working again, as I'm not entirely convinced.

Does the HDD show in DiskUtility?

Also, if it "just" the partition table that's gone, have a read of Repair a Mac OS X HFS+ Partition table.

I recently purchased a 2nd hand external drive, and accidentally powered of the drive while it was writing. Somehow the partition table went kafluey, but the partition was still there. Followed the above procedure, and all was good with the world.

Originally Posted by Biallystock

I have memories of fatal upgrades back at OSX 10.2 that wiped out many people's FW hard drives

Yep. Got bit by that one.

Originally Posted by mmulhern

Does the HDD show in DiskUtility?

Don't know, that's something I'll be checking tonight. Between TAFE and work I've barely had time to wipe my bum.

Ok, sitting at an iMac at TAFE and the drive is recognising in Disk Utility. Running a repair on it now, and it's taking FOREVER. At the very minimum, this is a good sign.