YouTube Extension gives 404 error

I have installed the YouTube Virtuemart extension and received a 404 Error on the page: recreationblack.com/index.php/products/b...hting-package-detail

I have put the following embed link in the link field:
<i-frame width="480" height="360" src="//www.youtube.com/embed/GMZMDjcfRZ0" frameborder="0" allowfullscreen>

What could I be doing wrong?

I finally figured out how to put in the link install code. No need to reply.

Thanks