Same me to
Delete the "com.apple.Aperture.plist"
Stefanos, you're seeing this under 3.4.2?
If it is the same problem, I'd suggest deleting Aperture and reinstalling it again, as detailed earlier in this thread. Again, throwing out the plist is not a permanent fix.
In one case to work with Aperture 3.4.1 delete the preferens.
And the other to the install 3.4.2 we were all clear it first
and then download it from the App / Purchases.
I appreciate that it may not be a permanent fix for all, but I have not had any problems since, so it worked for me without having to reinstall everything. I like those kind of fixes. ;-)
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