iMovie can't find my projects but the files are there

Great. Glad that that solved it.

Safe Mode verifies your start up disk and attempts to repair directory issues if needed. Since the issue was fixed when you restarted you probably had a cache or directory issue with your start up disk that Safe Mode fixed. (Those things happen for mysterious reasons -- possibly when you installed Mojave or some other major software.)

Here's a link that summarizes what Safe Mode is and does:

Use safe mode to isolate issues with your Mac - Apple Support

Best,

Rich

Try opening a new project in a newly created library. If it opens O.K. there, you may want to consider copying your old projects from the old library one at a time, from the iMovie Projects browser screen to the new library, and closing and opening the new library after each copy procedure. If the new library ceases to open after copying a project into it, that last project may be corrupted and causing the issue.

-- Rich

Hmmmm. That's odd. Your caches folder should look something like this, with an iMovie Backups folder in it:

When you said "I got a message that something was corrupt and needed repair, so I repaired it" what was the exact message and what did you do to repair it? Did you just click "repair library" in the message box?

Since your projects are still displayed in the library package contents, they obviously are there. For some reason the iMovie app is not reading them. You could try redownloading the iMovie app and see if that cures it. If the library itself is corrupt, then the above wouldn't solve it. However, since not even your Time Machine restored library works I am thinking that the problem could be with the iMovie app.

If the above is not it, as an experiment you might try copying (copy, NOT move) the contents of your current library package contents into the package contents of a newly created library, and see if the new library will read your projects. Be sure not to move or change anything in your original library package contents or you will cause more corruption.

To cover the bases, you can try other diagnostic procedures as well, such as:

1. Opening iMovie in a new user account, such as the Guest account on your Mac.

2. Booting in Safe Mode (see Help menu) and, after everything loads, immediately shutting down and rebooting in normal mode.

3. Running the Mac diagnostic program to rule out any hardware issues.

4. Run a virus scan.

How to use Apple Diagnostics on your Mac - Apple Support

All else failing, this might be a situation where you can consider taking your computer in to the genius bar at a local Apple store. They have testing equipment there and can do hands on testing that cannot be done on a user forum such as this one. Possibly they may suggest redownloading the operating system. Or maybe it is a virus.

-- Rich

Hi, Lewis,

There is no "rebuild database" command, unfortunately.

Try looking in the iMovie Backups folder to see if you can open a previous backup of your library. To get there, follow this file path: Go/Home/Library/Containers/com.apple.iMovieApp/Data/Library/Caches/iMovie Backups. When you get there you will see a list of previous backups of your library. Click on one that is dated just before the corruption happened. iMovie will open in that library. Look in the Projects browser (where the projects are displayed as icons) and see whether your projects are there and functional. If not, go to a library dated prior to your Mojave update.

-- Rich

Lewis,

Just as a curiosity, since this was probably a cache problem, try following the iMovie Backups folder file path and see if your iMovie Backups folder now is in the Cache folder, since it was missing before. The Backups folder is handy to have when projects disappear.

-- Rich

If it's working, no need to do anything more.

-- Rich