I'd say that for that certain video's MetaX doesn't do it the way Windows Explorer expects.
I don't think Microsoft will agree that it's their error, so better contact the maker of MetaX for a bug fix (or at least an explanation). On http://www.kerstetter.net/index.php/contact-me Rod says he's looking forward to hear from you.
Kees
I use MetaX (an MP4 Metadata editor) to add cover art to the mp4 videos in my library. It worked fine until just recently, when suddenly a few videos at random (it least it appears to be at random) showed up as the default "music-note-and-film-strip-with-hot-air-balloon" picture instead of their assigned cover art. I opened these files in MetaX, which said that they were displaying the correct cover art. How do I fix this? And why is it only happening with some of my mp4 files?

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