var popUpWin=0;

function showWindow(URLStr, left, top, width, height)

{

  if(popUpWin)

  {

    if(!popUpWin.closed) popUpWin.close();

  }

  popUpWin = open(URLStr, 'popUpWin','toolbar=no, location=no, directories=no, status=no, menubar=no, scrollbars=yes, resizable=yes, copyhistory=yes, width='+width+', height='+height+', left='+left+', top='+top+', screenX='+left+', screenY='+top+'');

}