Response from the site administrator
4kdownload, 21.09.2016
The link you've provided is private, that's why it can't be downloaded.
If you are the uploader of the video, please change video privacy settings to 'public' at least for the time of downloading.
Try downloading the video again when the changes are applied, it should work with no problem.
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https://player.vimeo.com/video/179449570