Today I experienced a very strange AE crash. After hitting ⌘D to duplicate a comp in the Project window, AE stalled. I waited about 15 minutes before force-quitting AE. After that, every time I opened the project, AE stalled.
I started a brand new project and imported the crashed project. AE was fine, until I highlighted one of the comps in the Project window. Then the new project stalled. I repeated the process with another blank project, and by trial and error, thought I'd narrowed down which comp was triggering the crash. All that AE would allow me to do was click and drag that comp into the trash. But only a SINGLE click, drag, and drop into the trash. If I clicked once and let go, AE stalled.
So after removing the "bad comp" and saving, the project seemed fine. Unfortunately I had to create that trashed comp from scratch, but it wasn't that big a deal. When things appeared to be back on track, I selected one of my comps and pressed ⌘D to duplicate...again, stalled.
THE SOLUTION (I think):
I repeated the process of importing the old project into a blank project, and trashing the problem comp. But out of curiosity I hit Undo. The trashed comp returned to the project in full working order.
I can't explain what caused this duplication crash or how this workaround worked. Maybe I am overlooking something major. But for now I'm happy that I didn't have to recreate the "bad comp" a third time. So I thought I'd post this in case anyone out there has run into this issue before, or if they might run into it one day in the future while under a tight deadline. Hope it's a help.
Here's a basic rundown of what's in the comp that was stalling the project. A couple solids with masks. CC Sphere. The Warp Effect. A camera, a light, and a couple time remapped precomps with loop expressions.