Last week, I got a call from a friend in dire straits: his MacBook would no longer boot and he hadn’t yet made a backup of an important documentary project he was working on as a freelance photographer. When I had a first look at the MacBook, it did start booting, the “progress rotor” did show up, but instead of presenting the OS X welcome screen, an icon appeared after a too-long wait, indicating the disk could not be found. Ouch.

So I inserted the OS X installation disk, re-started the machine courtesy of the Power button, and held down the Option key to be able to select the DVD as the boot volume. Interestingly, the Mac’s internal drive was among the boot volume options, but when launching the Disk Utility application from the OS X installation disk, the software could not find the internal HD. As the next step in the quest to revive this Mac, I booted it from a TechTool Pro 4 DVD and launched TechTool Pro, but, alas, the internal drive again failed to appear.

At that point, I tried to tell my buddy in words as non-dramatic as possible that it is, indeed, a Very Bad Thing™ if the physical drive fails to show up in disk utility software. That was when he asked if it would make sense to remove and then re-install the hard drive. To be frank, I couldn’t imagine that that would actually do much at all. Then again, this being a MacBook, that step wouldn’t take much time or effort and it wouldn’t hurt either, so we went for it.

Removed the battery, unscrewed the metal shield, gently pried the shield out of the battery compartment, slid out the hard drive, looked at it admiringly — “Wow, it’s that small?!” —, re-placed the drive in the computer, made sure it was fully seated in the drive connector socket, put the shield back in, fastened the shield’s three bolts, popped in the battery. And hit the Power button. And waited. And waited a bit more, until…

The Apple logo comes up on the screen, progress indicator starts indicating progress, (human) heart rate rises, and — the OS X welcome screen appears. And I hear a deep, a very, very deep sigh of relief from the person sitting next to me.

Just to be on the safe side, I ran the gamut of drive tests offered by TechTool Pro, including the surface scan, but there was no indication of a (looming) drive failure whatsoever.

Again, I would not have believed that this simple procedure would succeed in grabbing the drive from the cold hands of the data underworld, but it did. My guess is that, since in a MacBook, the drive just slides into place without any means of locking it down other than the drive connector itself, there is a chance that the drive can slide out of the connector when the laptop is bumped hard enough into, say, the edge of a table, so that the drive is disconnected from the logic board.

Whatever the actual root cause of this problem was: if you should ever run into a similar issue, do include this procedure in your trouble-shooting efforts before resorting to taking the machine to your dealer or sending it in for AppleCare. It takes just a few minutes and may be just what is needed to get the drive working again.