I successfully generated the video sitemap and it can be seen here http://dynamicsblogger.com/sitemap_video.xml. When I submitted this sitemap to Google, It returns with warning for almost all posts. The warning is
Url blocked by robots.txt.
Sitemap contains urls which are blocked by robots.txt.
Value: http://i.ytimg.com/vi/-0C6t_vFyX0/2.jpg

When I searched for this issue, I found the Thumbnail URL actually points to You Tube like the above example in Value field. These thumbnails are being blocked by You Tube through their Robots.txt. How can we get away with this issue and see the video sitemap working properly
Re: Video Sitemap Issue with You Tube blocking Thumbnails by Robots
« Reply #1 on: March 20, 2012, 10:30:23 AM »

please try to re-download generator package and install it, overwriting existing files, then regenerate sitemap.
Oleg Ignatiuk
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