When working on projects with AE renders, I'll often have to modify them after a draft is submitted. I'll render to the same file name so they'll automatically pop into the PP timeline. This will randomly cause an error in Media Encoder. The actual AE render is not corrupt. 99% of the time simply going back into PP and playing the clip will fix the problem and the same ME queue item reset will render correctly. Doesn't seem to matter if it's Alpha channel or not, always using either ProRes or DNx.

This is not a new problem - I've experienced this on multiple systems, Windows and Mac over the years, but I'm currently working on a 2020 iMac with a Thunderbolt external drive, AME build 15.4.1 PP 15.4.1 AE 18.4.1

It will either fail with Error retrieving frame # from xxxx or Frame substitution recursion attempt aborting after multiple attempts on file xxxx. Example of errors copied from Error log attached.