Can't watch a video from it constantly buffering windows 8

Hello, can somebody tell me what this means Given URL is not allowed by the Application configuration.: One or more of the given URLs is not allowed by the App's settings. It must match the Website URL or Canvas URL, or the domain must be a subdomain of one of the App's domains. That is what I got from Java console . ????
I have a brand new computer. when i try to watch something on you tube, dprograms all it does is buffer, buffer, buffer. makes me so mad. I thought maybe it had to do with java. I don't know. running windows 8 so I'm already lost. thanks