I was looking for the answer to this and the next steps should apply to .nfv too Repair Corrupt MP4 File with VLC player Open VLC Player on your PC and go to Media option; Now select the option Convert from the drop-down menu; Enter the file path of your MP4 video and hit the Convert or Save button; Under the Convert section select the input codec of your video file from the list; Select the Edit Selected Profile option and specify your profile settings; Now click on Start and let VLC repair your MP4 video file; You can change the file format of the video to AVI and fix it through VLC if the procedure as mentioned earlier does not work. Go to the location of the corrupt MP4 file and create a copy of it; Now rename the file format of the copy from MP4 to AVI. Open VLC and select Tools. After that click on Preferences from the list. Click on the Input option and select Always Fix which is right next to Damaged or iplete AVI file. Click on Save and you will be able to use the video file again.