Enable capslock while opening the project to suppress evaluation and rendering, then remove the offending keyframes.
I tried enable CAPS LOCK, open AE/project... error still pops out and locks the project
I need to finish this today....please!
If you can open OTHER projects with no problems, then create a new AE project and import the problem project into it. Sometimes that helps. Cross your fingers.
I managed to close and delete the bad preComp. All good now.
Ahhh! ...AE, very deep ...but fun.