I Have an error with quicktime
This is the error The document “REC000.avi” could not be opened. An unknown error occurred (-12842)
Quicktime X doesn't play avi files
Grab the last version of Quicktime Player 7 to view this file.
QuickTime Player 7 for Mac OS X v10.6.3 or later
It will be saved into /Applications/Utilities. If that also fails consider VLC or figure out what codec Quicktime 7 requires for that file.