Why won’t QuickTime play my MP4 videos anymore from my flash drive?
Mac mini, macOS 10.15
Could this have happened after upgrading to Catalina? There are several posts here about Quicktime not playing some videos in Catalina because of the 32 bit thing. Have you tried VLC or IINA?
Yes. It's just another player. It plays some files I can't get to play in VLC.
Do the videos play if you move them back to your hard drive?
One possibility is you thought the videos had fully transferred, but unplugged the flash drive while the files were only partially moved.
The flash drive may be transferring data too slowly. Does it try to play and then freeze?
They do not play if I move them back either. Looks like I’ll have to restore from time machine.
It does not. I get an error message saying the file I’ve chosen is not compatible with QuickTime. Which makes this very odd. Appreciate the help.
I tried VLC but haven’t heard of IINA. Is the second one another video player to try?
Yup. If they still don't play it's likely the 32bit codec problem people are having.
saved MP4 video to USB flash drive and now quicktime will not play it anymore
