While trying to use "Safari/Google" a blue "Warning" showed up in center screen: First, a "link" appears for "sentinelpowersafe" (I am not allowed to post the actual link in this "Warning" as I am a new member with only 1 post) Warning! Your computer is at risk of malware attacks. We recommend you to check your system immediately. Press OK to start the process now... I'd been to chicken to press "OK" as I suspect fraud or a virus, but I'd found nothig on the intenet or Apple websight. Meanwhile I am "blocked" from using "Safaro/Google". Please help!!