I have a set of movies that I created using ffmpeg. I use them for presentations in Keynote, and until today I had never had a problem. However, now when I try to drag them or import them in Keynote I am getting the message "The movie couldn't be inserted. This movie can't be added". I can see the movies using VLC and DivXPlayer, but they also fail when I try to open them with QuickTime Player. I have already generate them again, using different computers and different video extensions (mp4, m4v, etc), but the problem remains. I also downloaded a program called UniConverted to try to fix the error, but it isn't working. What is odd is that the error only appeared for the latest movies I am trying to add. The previous ones work just fine. Any help will extremely be appreciated as I am running out of time and I really need to put the movies in the presentation.