Never had that happen here either. Did have (not on this site) a message come up that looked just like Microsoft window warning me that a virus was attacking my computer - almost clicked on the "must do" button, instead shut down my computer. After thinking about it, wondered why the warning wasn't from my anti-virus software. Turned it back on and did a check using the anti-virus software and found nothing wrong. Now know 3 people who fell for it and once they clicked on the "must do" button, their computer WAS attacked and it costs them some big bucks to fix it. So who knows if what you have seen is real or not?