iTunes can't play quicktime movies

iTunes 12.2.1.16 is having issues playing Apple Quicktime movies. These items have played in all previous versions as far as I can tell. I've certainly never, ever had issues playing a outcome file within iTunes before and have never seen this quite bizarre error message.

For interest's sake, does anyone know when Apple stopped supporting their own video format? I can find nothing on the 'preferred' new format.

Much more importantly, has anyone had this error and found a fix?