Hi, I have an issue with all mp4 files, if I open a folder with mp4 and mkv files i can see the icon for every file, but if I select an mp4 file the right pane doesn't show anything, if I choose an mkv file I can see the preview and the play button. I tried deleting the contents of Cache folder but it doesn't make any difference, thanks.
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Preview not working for mp4 files (Catalina 10.15)
- Thread starter oscarodas
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Mac OS Catalina does not support playing MKV files natively.
My suggestion is to create a new user account and test if the issue with the MP4 files happens. If it does not then the issue is with your user account as something might be corrupted with it.
Another this to try is booting into safe mode and see if the issue happens in your user account. Safe mode prevents third party extensions from being loaded. It is a sort of sanity check.
support.apple.com
My suggestion is to create a new user account and test if the issue with the MP4 files happens. If it does not then the issue is with your user account as something might be corrupted with it.
Another this to try is booting into safe mode and see if the issue happens in your user account. Safe mode prevents third party extensions from being loaded. It is a sort of sanity check.
Start up your Mac in safe mode - Apple Support
To help determine whether an issue is caused by software that loads as your Mac starts up, you can start up your Mac in safe mode.
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I was not aware that Preview could play .mp4 files. But then, my immediate go-to installation is VLC Player anyway - which also handles .mkv, as far as I know.
(And I can't tell you the last time I opened QuickTime...)
(And I can't tell you the last time I opened QuickTime...)
Taz Mangus, I think it is a bug with my computer because I tried a different folder and al the mp4 files play with preview.
To Bazza1, yes I can use the preview to play my files in two different ways, first, if I highlight a file the right hang panel if you move the mouse over you will see a little play button, the second way is to highlight the file and press the spacebar, the file starts playing automatically. I hope you can see the files I attached.
To Bazza1, yes I can use the preview to play my files in two different ways, first, if I highlight a file the right hang panel if you move the mouse over you will see a little play button, the second way is to highlight the file and press the spacebar, the file starts playing automatically. I hope you can see the files I attached.
Attachments
I think I found the problem, the mp4 files with h264 codec play without issue, but the mp4 files with HEVC codec play if I press the space bar, but don't play in the preview panel.