Please offer video file retrieval suggestions.

So the .mp4 files were zero bytes, right? With limited info of the previous workflow it is not possible to guess why this happened. The best way to fix this is to restore from a backup or find out what workflow caused this.

We still don't know anything about your workflow. In 30+ years of working with video files I have never seen this abruptly happen. Were you doing something with the files in some editor or transcoder? Did the files used to play?

As for the Quicktime message, Quicktime is encountering something strange about the files. It may not know what is wrong but is just reporting it as a compatibility issue. Something in your process somewhere has corrupted these files so Qt just sees it as a compatibility thing, not detecting that the files are broken.

If you could put such movie sample in some cloud service (not Youtube because it often re-encodes movies) then we could better check what might be the problem.

Yes. They were full and complete video files. Weird as it seems it is like part or all of the content was ripped from the filenames.

When I try yo open the file/s I am given the message that Quicktime cannot open the files due to a compatibility issue (The file isn’t compatible with QuickTime Player.").

Upon looking closer it appears that most or all of the content of the respective file is gone. For instance- a 10 minute video may only have 5 seconds of video- or none at all.

I have tried opening the files with a couple different applications- all with no success of seeing my original video files.

I have backups but the backups are no good. They are copies of the problem files, unfortunately.

I have 234 files that are having this issue. I have never seen anything like this. I am a seasoned user and retired global admin but this has thrown me a curve ball.

Thanks for your input.

Yes you are correct- QT apparently can't open the files due to compatibility. But, I believe the incompatibility is somehow being/has been caused by some sort of data loss. And, it is strange as you said.

It is almost as if it was virus-like.

I have hundreds of video files. All played without issue. Then I noticed there were a number of files like this. I have 234 video files that have the same issue. I have never had an issue like this to happen.

As far as work flow goes, I created the videos, edited all in iMovie or QT and saved them to my home directory. Then they were backed up. That is pretty much it as far as workflow.

Also, in answer to your question- the files went from complete file to 0-minimal amount number of megabytes (0-10mb for example).