Use VLC Media Player or Windows Media Player.
If this is a personal video (like a security camera clip or a screen recording), it's best to rename it to something recognizable: Select the file and press (Windows) or Enter (Mac).
Change "Ajb08406" to a descriptive name (e.g., Vacation_Clip_01.mp4 ).
How to add more information to a video file or .mp4 file? - FileBot
Since the name is non-descriptive, you can check the file's metadata to learn about its origin:
If you found this file online or received it from an unknown source: