Mac screen recording corrupted or missing? QuickTime and Screenshot fixes
By the FixMP4 engineering team · · 6 min read
macOS has two built-in screen recorders: the Screenshot app (Shift-Command-5) and QuickTime Player (File, New Screen Recording). Both write QuickTime MOV files, usually H.264 video with AAC audio when you record a microphone. If the recording ends abnormally, you may find either no file at all or a .mov that refuses to open.
Why the file is missing or broken
During recording, macOS writes the movie progressively and finalises it, including the moov atom index, when you stop. Things that interrupt that:
- The disk fills up (long Retina-resolution recordings are large).
- The Mac sleeps or the lid closes.
- QuickTime or the Screenshot app crashes, or you force-quit it.
- A power loss on a desktop Mac, or a battery that empties on a laptop.
- Logging out or restarting with the recording running.
Finding the file
- Check the save location you chose in the Screenshot toolbar (Options, Save to). The default is the Desktop.
- Use Spotlight or Finder search for files of kind "Movie" modified today, sorted by date.
- QuickTime autosave: QuickTime may keep an unsaved recording in its autosave area; reopen QuickTime and look at File, Open Recent, or the window offered on launch.
- Search for large recent files: in Finder, File, Find, add "File size is greater than 100 MB" and "Last modified date is today".
If you find a .mov that will not open or shows 0:00, it is probably missing its index.
Rebuild the index
- Make a reference recording with the same tool, the same display (or the same selected area size), and the same audio option (no audio, internal microphone, external microphone). Ten seconds is enough.
- Open the repair tool and add the broken MOV and the reference.
- Watch the free preview and export with a subscription.
Screen recordings often use a variable frame rate (fewer frames when nothing moves). After a rebuild, timing is computed at a constant rate, so a mostly static recording can play slightly faster or slower in places. Audio, measured from the AAC frames, stays accurate. If precise timing matters, see audio out of sync after repair.
Third-party recorders on Mac
- OBS on macOS: see recover an OBS recording; switch to MKV or hybrid MP4 to avoid this in future.
- Loom, CleanShot, ScreenFlow, Camtasia: each has its own recovery behaviour; check the app's recovery or library folder first. ScreenFlow and Camtasia use project formats that need the app.
- Zoom recordings: see Zoom recording failed to convert.
Prevention
- Keep at least 20 GB free before long screen recordings.
- Prevent sleep during recordings (System Settings, Lock Screen and Battery or Energy, or a utility like Amphetamine).
- Record a smaller area or a lower-resolution display if you do not need full Retina resolution.
- Split long sessions into parts.
What is supported
H.264 and HEVC MOV files with AAC audio are supported. ProRes screen captures (an option in some tools) and recordings with PCM-only audio are not.
More background on MOV files: repair a MOV file and MP4 vs MOV.
Frequently asked questions
Where does QuickTime save an unfinished screen recording?
QuickTime and the Screenshot app write to a temporary location during recording and move the file when you stop. After a crash, check the chosen save location, Desktop, and QuickTime's autosave locations; Spotlight searches for recent .mov files help.
Can a corrupted Mac screen recording be fixed?
If you have the .mov file and it is large but will not open, yes: rebuild the index with a short reference recording made with the same tool and settings.
Why did my screen recording stop?
Common causes are a full disk, the Mac going to sleep, a crash of the app, or the system killing the recording when memory or disk space ran out.
Have a broken recording right now?
Diagnose it and hear or watch a free repaired preview. Nothing is uploaded.
Open the repair tool