|I had the same problem, not just youtube but any videos. I did everything uninstalling, empting the browser cache, making sure active scripts were enabled. I was able to fix this problem by uninstalling IE 8 which rolled back to IE 7 by default. I then noticed after I opened my browser that I had an Icon at the bottom of each page (add-ons) which I had several add-ons disabled. I enabled the add-on and I was back in business.|
I'm sure I took the long way around this problem but non the less it's fixed.
Hope this helps.