Stop Aperture 3 from freezing when quitting
Since upgrading to the latest version of Aperture 3, I started experiencing a bug where Aperture would freeze when trying to close down. Aperture would say that it was “updating information for sharing previews.” But it would simply hang on that screen and not go anywhere until you were forced to Force Quit the application.
This is a pretty severe bug for anyone working regularly in the application, and after becoming irritated that it was happening on a regular basis I decided to do some investigating.
After doing some searching on Apple’s support discussion forums I discovered that you can solve this quickly and easily by going to Aperture > Preferences and then selecting the “Previews” tab. Once on that screen, which is pictured bellow, simply set “Share previews with iLife and iWork” to “Never.”
After that you should be all good to go and Aperture should close without hanging or freezing.