function openWindowCentered(theURL,winName,width,height) {

if (document.all) {
   var winl = (document.body.clientWidth - width) / 2;
}
else if (document.layers) {
   var winl = (window.innerWidth - width) / 2.1;
  }
var wint = (screen.height - height) / 2.7;
   features =
'width='+width+',height='+height+',top='+wint+',left='+winl+',toolbar=no,location=no,status=no,menubar=no,scrollbars=yes,resizable=no'

   window.open(theURL,winName,features);
}