Mac won't recognize External HD - FAT32


macrumors newbie
Original poster
Dec 6, 2009
Richmond, VA
I formated a new 1.5TB WD hard drive, using the eSATA cable - in the FAT32 format so I can use it on my PC as well. (It was formatted on the MAC)

I was working on the Hard Drive via eSATA and the express card. Then the Hard Drive was accidentally unplugged. Subsequently, my MacBook Pro didn't like that and gave the warning message to properly eject ... too late! I restarted the MAC and it still won't recognize it - I've tried eSATA, USB, firewire- and nothing. The hard drive was all 3 connections. So, I tested the HD on a friend's MacBook Pro and the hard drive is recognized without any hesitation and it works fine. So, there is nothing wrong with the Hard Drive - its my MacBook that won't recognize it.

The HD won't even show up in disk utility of my MAC. I've restarted many many times and I've tried every port available. Any suggestions??? Thank you!!!


macrumors 68000
May 31, 2004
I'm not certain what's going on, but you can quickly determine if it's a software issue on your computer:

Boot from your OS X Install CD by restarting your computer with the CD in holding down the C key. When it gets to the language selection box, click continue. Then go up to Utilities -> Disk Utility and see if it will recognize the drive plugged into a port. If it does, you know it's some corrupt file or bad setting with your OS X installation.


macrumors newbie
Dec 6, 2009
I had a very similar problem; external HD working fine, then couldn't be recognized.

After scouring the forums and trying everything, a guy at my local Mac reseller suggested it was likely a directory problem, created by improperly disconnecting.

He suggested Disk Warrior would likely fix the problem.

Got it, ran it, no more problems!


macrumors newbie
Dec 7, 2009
I'm not certain if Disk Warrior would work in this particular case because the drive is recognized on the other computer and the drive doesn't show up at all in Disk Utility on your computer.

I would give LeeTom's suggestion a shot before dropping $ on Disk Warrior. You can always try it down the road.

The drive (and I mean the physical drive, not necessarily the partition) should show up in Disk Utility regardless of the state of the partition on the drive.


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