Paul writes: When my son updated to Yosemite on his Mac he lost the entire iPhoto library. He is sure the photos are there somewhere as he keeps finding photos as files (on his hard drive). Can you please help?

Hi Paul! I feel your pain—or your son’s pain, that is. iPhoto on my Mac used to freeze a couple of times a week, until finally it crashed and burned, leaving thousands of blank boxes where my photos used to be.

Like your son, I could see my images sitting on my hard drive, but iPhoto stubbornly refused to display them.

iPhoto First Aid options

You can turn on iPhoto’s “First Aid” mode in just a few clicks.

The good news, though, was that all my carefully curated iPhoto library wasn’t gone for good—and with a little time, effort and luck, your son may be able to restore his iPhoto library, too.

Before you do anything, though, back up your hard drive, using either Time Machine or another method. That way, you can turn back the clock if anything goes wrong during the (potentially extensive) iPhoto restoration process.

You’ll also want to set aside some serious time for your iPhoto repair work. It took several hours for iPhoto to fix my photo library, for example, and while I was still able to use my Mac while the the work was underway, your system may feel a little sluggish during the procedure.

So, all set? Let’s get started…

First, let’s turn on iPhoto’s “First Aid” mode. Press and hold the Option and Command keys, then launch iPhoto. In a few seconds, a panel should appear with a quartet of maintenance options: “Repair Permissions,” “Rebuild Thumbnails,” “Repair Database,” and “Rebuild Database.”

So, which option should you start with? My suggestion: start with “Repair Permissions” and work your way down the list, stopping after each procedure to see if your photo library has reappeared.

As you move down the fix-it list, the repair work gets more and more involved, with “Rebuild Database” being the most intrusive and labor-intensive (on iPhoto’s part, not yours).

In my case, my iPhoto library came back to life after the “Repair Database” step, so I didn’t bother with “Rebuild Database.” And once all the first aid was finished, my copy of iPhoto ran better than it had in months.

Give that a try and see if it works, Paul. Still no luck? If so, it might be time for your son to pack up his Mac and take it to a Genius Bar for expert help.

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