Make sure you know all of the risks involved with that last option (add to trusted sites). This will allow greater access to your computer by not only YouTube but other sites that YouTube is linking to. It can make your computer more vulnerable to malware delivered via drive-by, including ad networks that are used by YouTube. And since this is not a secure connection (http:// vs https:// ), it cannot perform verification of the site. This means that you are more vulnerable to MITM and DNS injection attacks. Only make the change if you are willing to accept the additional security risks.