'Illegal Command Sequence' followed by 'Layer does not have a source'

Report · Nov 11, 2024

For a while now, After Effects has been loading up to 99%, and then crashing whenever I open a project. Normally, I just keep trying and eventually it works. This issue persists across every single project.

However, today, this one project refuses to open and hits me with a new error 'Illegal Command Sequence', which takes loads of tries to close the pop-up window, and then it's followed by multiple 'Layer does not have a source' error messages.

I can open the project on another computer, which is strange. I opened it up and Reduced the project (from 75MB to 25MB in size), but this hasn't helped.

Does anyone have a solution for either of these errors? I have tried:

• Removing plug-ins (from ScriptUI Panels folder)

• Starting in Safe Mode

• Reduced the project

• Cleared all Cache

• Importing the project into a new, empty AE project

• Opening from 'File > Open...'

Computer specs:

• Mac Studio M1 Max

• 64GB RAM

• MacOS: macOS Sequoia 15.0.1

• Assets are stored on an external SSD Hard Drive

I am using After Effects 25.0.1. Any help would be greatly appreciated!!

Report · Jan 17, 2025

Same problem here. I found some threads about deleting .lst files. They were all tailored for window users but I searched them out and deleted them and it worked...for a few days. Still having this issue

Report · Feb 27, 2025

Hey guys. We ran into this problem now the second time. And for some reason we could not get this corrupt file to open on two machines, but we could open it after crashing and starting After Effects in safe mode with disabled 3rd Party Plugins. There was not much in the scene. 1 mp4, 1 mov and one adjustment layer. We found out that the mov was causing the problem. It was encoded with an Aplle Pro Res 422 HQ. We had the same video also as an mp4. Directing the comp to the mp4 instead of the mov solved the problem. We re-encoded the file to a different codec and it worked.

This is the second time a weird codec issue caused those crashes and alsmost hopeless situations. So one suggestion for future would be to remove the linked files from their destinations or rename them and let After Effects open with lost connection to the media. You can then step by step re-import the footage, save and re-open to see if it still crashes or its good. This was our way to find out.

Cheers.