Embedded YouTube videos not displaying in IE
I'm having problems with YouTube videos embedded into a presentation. The problem only seems to exist in Internet Explorer (I am using IE8 to check it - not tried with any other versions of IE). Rather than displaying the video, I get a white box with the word "advertisement" in the top left corner (see attached screenshot).
I've used the embed code from this article, which in this case is http://www.youtube.com/embed/C6OC_IJwP3o?rel=0. I think it may be a problem with the embed code, rather than anything specifically in AP, because when I visit that link in IE8 it shows the same thing.
I'd be grateful for any suggestions. Not using IE is the obvious one (as usual...) but this is unworkable as all of the PCs on campus have IE as the officially supported browser.
UPDATE - It seems to work on some PCs with IE8 but not others. I can't find any reason why it appears differently.