I've done a lot of searching but haven't been able to find the answer to a problem I'm having. I have several projects in Aperture 3. I just noticed that three of those projects now have duplicates. If I rename a project, its duplicate also gets renamed. So, they're linked. If I go to delete one of the projects, I get a scary warning saying the images are referenced elsewhere. How do I get rid of these duplicates? Was it something I did?
1) Back up your aperture library.
2) Hold down "Command" and "Option" at the same time, while you click on the Aperture application to run it.
3) You are given a dialog box with the option to "Repair Permissions", "Repair Database", or "Rebuild Database". Start with "Repair Database", and see how your library looks when that is done.
4) If that didn't fix the issue, try "Rebuild Database" - that may be slow (it took a 2TB Aperture library I have about 30 minutes to rebuild) but should resolve the issue if nothing else does.