If MP4s import into editors (like After Effects) as green or broken, try disabling hardware-accelerated decoding in the application preferences. Managing Large Numbers of MP4 Files
Use file management software to organize large volumes of video data to prevent "metadata" issues where the computer cannot identify the video/audio tracks. If you can tell me more about: 56 mp4
Use tools to check if files are truly "unidentified developers" if they are downloaded from the internet, as Apple devices sometimes block them by default. If MP4s import into editors (like After Effects)
If you are streaming or opening files from a cloud service, check your router or re-download the file to rule out corruption. 56 separate MP4s):
If you are dealing with a bulk set of videos (e.g., 56 separate MP4s):