While the file extension is .mp4, the data inside might be encoded with a specific codec like H.264. If your player doesn't have the right "key" to decode it, the video remains a black screen.
Do you have about what happens in the video so I can make this post more accurate ? MP4 files explained: How to open and use - Adobe
If the file was partially downloaded or pulled from a dying hard drive, it might need a video repair tool to bridge the data gaps. The Verdict b125.mp4
On sites like Reddit’s r/LostMedia, files with these types of names are often the only remnants of deleted YouTube channels or shut-down livestream archives. Why Can’t I Open It?
Below is a blog post written from the perspective of a blog, treating the file as a cryptic discovery. Mystery of the Archive: Decoding "b125.mp4" While the file extension is
If you’ve come across a version of that won't play, you’re likely dealing with one of two things: a codec issue or file corruption .
The name "b125" doesn't give much away at first glance. In the world of automated file naming, "b" often stands for "Batch," "Backup," or "Buffer." MP4 files explained: How to open and use
For now, remains a digital ghost. Without a confirmed origin, it serves as a reminder of how much of our digital history is saved under names that mean nothing to the public, but everything to the person who hit "Save."