The -av-1, -av-2 files mean that the drive you saved to was Fat32, and had a 4GB file size limit. When you exported your movie, instead of it saving it as say, one 16GB movie, it had to break it up into 4 chunks...-av-0, -av-1, -av-2, -av-3. If only the original file...the first in that sequence, exists, and the others are gone, then it won't open. It needs those files to complete itself.
As to why it opens in Quickview...got me there.
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