Rather than a bug in iPhoto, this seems to be symptom of database corruption and folks have had goo results with a Back Up and followed by rebuilding the library: hold down the apple and option (or alt) keys while launching iPhoto. Use the resulting dialogue to rebuild. Choose to Rebuild iPhoto Library Database from automatic backup.
Had the same problem with some thumbs. Discovered it was the way I cropped them in iPhoto, perhaps in a "non-constrained way. I opened these images in PS and cropped them to a standard 5x7, 300 ppi and saved. Now they open fine in iPhoto. May have to do with Quicktime handling.
Entire library (all photos) are visible in normal mode, when you double click them to enlarge and during slideshows. The images will not however, load during editing mode. A white box appears where the photo should be. It does not matter whether the setting is Full-screen editing mode or not, either way it will not load. I have already read the Apple Article: HT1261, followed all the suggestions but the problem still occurs. I Re-installed iLife, tried using a different Library, another hard drive and another account. No matter what I do, I have the same problem.
My entire library (all photos) are visible in normal mode, when you double click them to enlarge and during slideshows. The images will not however, load during editing mode. A white box appears where the photo should be. It does not matter whether the setting is Full-screen editing mode or not, either way it will not load. I have already read the Apple Article: HT1261, followed all the suggestions but the problem still occurs. I Re-installed iLife, tried using a different Library, another hard drive and another account. I have deleted the com.apple.iphoto file in preferences and even repaired permissions on ALL MY HARD DRIVES! No matter what I do, I have the same problem.
Has this issue been solved? I am having the same problem with the photos not showing in edit mode, however they display in thumb size. Also the photos won't display in slideshow. I've rebuilt the database as suggested but this has done nothing. Any help would be appreciated.