MP4 is a multimedia container format with many kinds of video and audio codecs. If your MP4 file contains a VLC unsupported audio or video codec, VLC won't play it. Check out the VLC supported Video/Audio format of the media player. Then, what to do if you want to open and play all MP4 files with VLC? Here, we offers you a solution to help you solve the “MP4 cannot playback on VLC” issues. ...