I'm using Windows 10 and the newest version of APE. But the problem is not limited to one MP4 program, and yes, all other programs can read it. And it’s not limited to one MP4 files – it’s *all* files now. Something is very wrong. And as noted, all the other Adobe programs can read all photo files, and I’ve cleared the cache in APE to no avail. Moreover, as noted, I’ve twice uninstalled and reinstalled it.