In the event of the app terminating unexpectedly, you may end up with a non-finished video file that cannot be opened by Quicktime. This article provides some tips/tools that may be useful in recovery of the media,
Locating the Damaged File
in OSX 10.7.x or later, iShowU will record directly to the final movie location. Therefore, when searching for damaged files, look there, not within the temp folder.
Attempting a repair
Here's some recovery tools that you can try:
- Video Repair (http://grauonline.de/cms2/?page_id=5)
- Youdot (http://www.yodot.com/mov-repair/quicktime-mov-file.html)
- Treasured (http://aeroquartet.com/movierepair/download)
Most of these tools require a good file to work from. So the very first thing you should do is create a 4-5s recording using exactly the same settings that you used when creating the original movie. This will be used as a source "correct" movie to the repair tool.
From there, follow the instructions of each tool (any one should work, but I've listed three so there's some choice).
Note: SWB has no affiliation with these app providers, they are listed here as the result of a Google search.