Double-click the file to open it in QuickTime Player .
Use File Explorer to locate the file, right-click it, and select Open with to choose a player like Windows Media Player or VLC.
MP4 is one of the most common formats for streaming and downloading because it compresses high-quality video into a relatively small size.
It is an international standard that works across almost all devices, from smart TVs to gaming consoles. Common Troubleshooting