Where are these MP4s coming from and where are you saving them to? And how are you using Premiere Elements to send the files to these locations?
It's not quite clear what steps you're taking and what specifically is happening.
I am experiencing the same problem with just one file.
File Type: GoPro MP4
This is the same format I've been using for a long while and never experiencing this issue.
The MP4s are saved to a 4tb external hard drive where they're imported using a project's Add Media feature.
This particular project will import other MP4s with no errors from the same external hard drive. The file in question, plays in media players, I typically use VLC, and appears to have no known errors yet the generic importer error remains.
It is also a work file so I don't want to have to re-film the video which sometimes has to happen.
Thanks for the help.
Yours is not the same situation as the original poster's, going bigger.
In your case you're likely dealing with a file with a variable frame rate, something you can remedy by converting the file with Handbrake.
If you'd like to discuss this further, please start a new thread so that your conversation doesn't get confused with smit's.