Loss of photos resulting from rebuilding the iPhoto library?

Question

On behalf of myself and Susan Pease: Can following the directions to rebulild the iPhoto library (by holding down the option and shift keys while opening iPhoto) result in a loss of the photos? Is there some precaution we should take to make sure that the photos are not lost?

Answer 1

Hi, aag. I didn't make myself clear, at least not to you. Inside your personal Home folder on your hard drive is a Pictures folder, and inside the Pictures folder is an iPhoto Library folder. You can see this folder structure by visiting your Home folder in the Finder. What I was advising against in my prior post is opening that iPhoto Library folder in the Finder and adding, deleting or moving any of its contents. Don't do that.
When iPhoto is open, what it displays is the contents of that folder. It expects to find them exactly as they were the last time you closed iPhoto, and it counts heavily on finding them structured exactly the way it structured them the last time you ran it. If you have changed anything in there while iPhoto wasn't running, you're going to have trouble: iPhoto won't load the library, it won't display all your pictures, some of your albums may be missing or incomplete, etc.
"Nobody has any business in there except iPhoto itself" means that the only methods you should use to tweak, edit, delete, import, copy, export or organize the photos in your iPhoto Library folder are the methods offered by iPhoto itself when it's running†. When iPhoto isn't running, leave your iPhoto Library closed and stay out of it.
† Note that, at least in iPhoto 4 (I'm not familiar with iPhoto 2), these allowable methods include the designation of a different application for use in iPhoto's Edit mode, allowing you to use Photoshop, GraphicConverter, etc. to tweak your photos without removing them from iPhoto's control. But under no circumstances should you import a photo from your camera into Photoshop or GC and then save it in your iPhoto Library folder without opening iPhoto and importing it properly. And similarly, you should never open one of the photos in your library with another application, make changes to it, and resave it in the same place (or worse, a different place in that folder) without going through iPhoto to do so.
If you can train yourself to think of the iPhoto Library folder as a locked box to which only iPhoto has the key, you'll be doing yourself a big favor.