This naming convention ( video_YYYY-MM-DD_HH-MM-SS.mp4 ) is the default format for videos saved from Telegram. Check your "Telegram Desktop" or "Telegram Video" folders.
Use VLC , as it can play almost any .mp4 format regardless of the internal compression. Download File video_2022-06-10_09-34-27.mp4
Before opening any downloaded file from an unknown or forgotten source: This naming convention ( video_YYYY-MM-DD_HH-MM-SS
If the file won't open in your default player, it may be using a specific codec: Download File video_2022-06-10_09-34-27.mp4