You need the Apple QuickTime Pro codec or a QuickTime alternative codec to convert QuickTime movies.

Because there are so many iterations of the QuickTime format you may have to rename your source file to get it to load. The below files, all named with the MOV file extension, were downloaded from a site that hosts movie previews.

The MOV extension however is the old Apple naming convention so Fx MPEG Writer compares it to the expected MOV structure and fails with the below error.

The structure of this movie in fact matches the later version of QuickTime which used the QT file extension. Renaming the file may produce a warning from Windows. You can name the file back to MOV after conversion.

With the QT extension the file loads.

In this case the source movie is not a standard MPEG-1 size so we will set the aspect ratio of our new movie to match the source size.