If you prefer using your usual video player (like VLC or KMPlayer), you can convert the file to a standard format:

: Usually contains the official conversion utility for DAV to MP4/AVI.

To play DAV files (proprietary video from CCTV/DVR systems like Dahua), you generally need a specialized player or a converter since standard players like Windows Media Player often fail to open them. Recommended DAV Players (Free Download)

: A versatile free player for Windows and Mac that supports 4K and DAV playback without additional codecs.