Apple – Support – Discussions – iphoto doesnt work …. Terence Devlin solution worked!
1. Put the iPhoto.app in the trash (Drag it from your Applications Folder to the trash)
2. Go to HD/Library/Receipts and remove any pkg file there with iPhoto in the name. On 10.6 those receipts may be found in the Finder using the Go menu and selecting Go To Folder
In the resulting window type
If you purchased an iLife Disk, then iPhoto is on it.