: You can use tools like MediaInfo to see exactly how the file was encoded. 4. Security Warning

: The alphanumeric string acts as a "fingerprint" (hash) for that specific file's data. 2. How to Safely Open the File

: The VLC Media Player is widely recommended because it includes the necessary codecs to play almost any MP4 file, even if it is slightly corrupted or uses unusual encoding.

: Right-click the file and select Open with > Windows Media Player or Movies & TV .