I keep the "accept cookies" box unchecked except for when I do need to allow them (no 3rd party cookies accepted). I never close the preferences box until I have unchecked the "accept cookies" box and delete those needed to be allowed cookies. Lately, about once every 5 days or so I find this box checked when I open the browser which I open every day. I have Norton security, so assume I would know if there were some infection? Some help please.