I am importing old photos and videos (most from iPhone originally) exported from iPhoto into a new Photos Library. Photos export and import fine, but videos exported from iPhoto work fine (they play) but do not play (0:00) after they are imported into Photos.
Just in case there were background processes that needed to complete for the import, I waited 12 hours then checked again, and but the videos were still 0:00 length.
I verified the source videos on the file system played just fine.
Both iPhoto and Photos apps are the latest versions as of this questions.
How might I solve this problem?