Unblock Restricted website in Explorer 8

I once blocked www.youtube.com website. I added it in Restricted zone. Now I want to remove this file but I can not find the name in the list.

When I try to run any video I get a message.

“Hello, you either have JavaScript turned off or an old version of Adobe’s Flash Player. Get the latest Flash player. ”

I have updated Flash Player but still not success.

Can any one help how I can get back my youtube website.

Regards
Tariq