Hi I regularly play Citiville on Zynga.com and recently I have this ad's on my screen running from top to bottom (rectangular) in shape blocking part of the screen. It has an x on it but it does not allow me to close it if I try and close it it takes to me to this screen. It is really frustrating me. I think it is an embedded virus and I don't know how to get rid of it. I have run virus check but it is not finding anything. Please help me.