If an MP4 video file won't play in Final Cut Pro, this can only mean that you've imported the file into the program incorrectly. You can't just drag the file into the main program window and drop it like you can with media playback programs. Final Cut Pro needs to render the file so that all of the frames and audio are available for both playing and video editing purposes. Importing the file correctly will fix these issues.

Click the Final Cut Pro "File" menu.

Click "Import."

Select the MP4 file you want to properly import using the "Import" dialog box. Click "OK." Final Cut Pro will render the completed file and place it in your main program window. The clip will play properly.

• MP4 Files Won't Play in Final Cut [09/20/2010 05:03:23]