Some of my .mov files will show their thumbnail in finder and others do not

Hi guys,

Fairly new to the apple family. I have a problem with thumbnails, .mov to be exact.

So we are a broadcasting company that works with media.

Why is it that some of my .mov files will show their thumbnail in finder and others do not.

All my .mp4 files show.

I have tried to delete that apple.finder.plist in ~/Library/Preferences/ but to no avail.

I am at my wits end. Any help will be appreciated.

Thank you in advance.

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