After backing up macOS 10.11.3 - .MOV files will not play. Backup was with Acronis 2018 to local HD.
OS reports "Cannot Play Video" Photos cannot play this video because it uses an unsupported format."
The OS was not restored, only backed up. macOS reported after backup - had to 'Restore' photo library
Other format files (e.g. .mp4) play OK. .MOV files OK on my iPhone iOS 11.2.6
How can I ?? these .MOV files to play?