We have gone on our comp after a while and tried to open Firefox . When we do we get a message "Firefox is running close app or restart comp . " Now the thing is I was on it earlier and closed it with the close button . Then say checked mail , or looked at pictures on my comp . Then I would want to use the browser again and when I tried to access it I get that message . Rest assured it had been closed . This issue did not happen until I downloaded Firefox4 . We did not have this problem with the earlier versions of Firefox .