VLC's repair option fixes AVI only
VLC has a setting under Tools > Preferences > Input / Codecs called "Damaged or incomplete AVI file", which can rebuild an AVI's index while it plays. It does nothing for MP4 or MOV. Those formats keep their index in a different place, the moov atom, and VLC has no tool to rebuild it.
Converting the file in VLC (Media > Convert / Save) doesn't help either: VLC must read the video to convert it, and that's the step that fails.
What VLC's failure tells you
| What VLC does | Likely cause |
|---|---|
| Nothing happens, or "Your input can't be opened" | The MP4 or MOV has no index: the recording or copy stopped early. |
| Plays a few seconds, then freezes or jumps to the end | The index is there but the data after some point is missing or damaged. |
| Sound plays over a black or green picture | The video stream is damaged, or the codec settings are wrong. |
| Plays fine in VLC but not elsewhere | The file is fine; the other player lacks the codec. |
Repair the file
- Open the video in the checker on this page. Your browser reads it from your disk; nothing is uploaded.
- The free check tells you whether it found the pictures and sound, and how much of the recording it can rebuild.
- Watch the free 15-second preview of your own footage.
- Download the full video for $4.99, or with a plan; $3.99 for one video in the Windows program. If it doesn't play, write to support@nasrtech.dev and we'll look at it with you.
The checker repairs MP4, MOV and AVI from phones, action cameras, drones and dash cams. For AVI it rebuilds the index from the file's own headers, the same job VLC's option does on the fly, but it writes a file that plays everywhere.
The engine in two dates
- 16 October 2026: AVI repair fixed in the Windows program; the browser checker reads AVI files from dash cams and DVRs with Motion-JPEG or H.264 video and PCM or ADPCM sound.
- 12 October 2026: the same engine runs in the browser and saves the same file, byte for byte, as the Android app.
What a user wrote
"Only app that actually works and it's incredibly fast as well! Totally worth paying for the premium, and it's surprisingly cheap." (Google Play review of the Video Repair app for Android, same engine, October 2026)
