Rebuilding the iPhoto Library
From Apple: "Sometimes rebuilding the library may resolve issues such as the library appearing to be unreadable, missing photos, or other issues related to reading the iPhoto library structure." http://support.apple.com/kb/HT2638
- Backup the iPhoto library first: Backing up iPhoto
- This is the procedure in brief. Please read (in full), Apple's guide: http://support.apple.com/kb/HT2638
- Quit iPhoto if it is open.
- Hold down the Command and Option keys on the keyboard.
- Open iPhoto.
- Keep the keys held down until you are prompted to rebuild the library.
- A dialog will appear with rebuild options. Select the options you want to use.
- Click Rebuild to begin the rebuild process. This may take a few minutes to complete.