You will find them in your home folder > library > Preferences
You are looking for com.apple.iphoto.plist
Drag it to the desktop and launch iPhoto
A new pref file will be created with default settings.
P
I wanted to import photos in iphoto 5 but it doesn't pop up a dialog box asking if I wanted to import duplicates unlike my previous version. How do I make iphoto show this dialog box again?

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