Internet Explorer uses the AOL Certification technology for security purposes. These certification techniques help the user to avoid malicious and unsafe websites. There may be some issue in the setup, and because of these websites of AOL may be shown as Untrustworthy and Malicious. If you are facing any issue, then your browser can use the benefits of the AOL certification.
Source: http://start-mcafee.com/how-to-fix-aol-certificate-not-trusted-error-message/