Where exactly did you or what context can you share to help narrow this down?
In some database dumps—such as specific SEC EDGAR filings —long strings of random characters may inadvertently contain standard video extension labels like "MP4" combined with nearby alphanumeric sequences, despite not being actual video files. g9169.mp4
If you cannot open the video safely, you can upload the file to a local metadata tool like ExifTool to see the origin device, the date it was created, and the specific camera used to shoot it. Where exactly did you or what context can
If you possess this physical file on your computer and want to figure out what is inside it, follow these steps: the date it was created