I have had LR6 failing to export certain files over and over again even though the RAW files were not corrupted.
This happened all the time with Adobe Bridge. I found that it only fails the export with Adobe Bridge opened to the same folder that the files are exported to.
As a workaround, I tried clicking on another folder in Bridge. It worked, the files are exporting as usual.
Hope this helps someone. It was driving me crazy for a while.
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