Q: iMovie error message "The operation could not be completed"

I had the same problem. I created a new event, and then created the new movie with that event when it asks for the name and event for the new movie. It worked. I hope this helps.

My problem was because I had moved my Movies folder from the system drive (which is an SSD) over to another drive with a larger capacity. I then created an Alias in my home folder.  Turns out this is what was causing the problem. I shoulda known. Some apps absolutely hate this. iMovie, being the dumbed down garbage that it is, simply MUST have it's library in a certain folder, apparently. Would be nice if we had a choice about it.

I find Premiere Elements is actually the better (and friendlier) program. However in this case, I had to slum it with iMovie due to the Quicktime file I was working with.

Hey, figured out an easy fix to this problem.

All you need to do is have an event available that the project can pull clips from. So, first, you need to create an event.

Pesky, though, because you can only create an event when you have clicked on "iMovie Libraries" in the left hand bar. Give that button a right click and you will see "New Event" a now viable option. Once you create an event, you should be able to add a project to that event.

Hope this helps! I didn't see anyone with this answer on the internet.

OMG!!! THANKIU SO MUCH!!! This works!!

Good job!!!! So much easy, thank you!!!!