wndChild=null; function MM_openBrWindow(theURL,winName,features) { if(wndChild!=null) wndChild.close();//if Child window is opened, close that window. //Open the child window wndChild=window.open(theURL,winName,features); } //This function will be called in 'onUnload' //Eg: function ClosingTheChildWnd(){ //wndHandler.sayThanks(); wndChild=null; }