Thank you for this feedback.
I tried accessing the page in question and the video on it and I was not able to reproduce the described issue. Your feedback has been forwarded to the team responsible for Telerik.tv. I would suggest that you try again now as there could have been an issue in the site at the moment you have tried to access it. This issue seems to have vanished, so now you should be able to watch the video as expected.
Let me know if you continue getting the same message.
the Telerik team