echo "<script type=\"text/javascript\">
alert (\"fehler gefunden\");
t=window.open (\"mahnung.php\",\"Zweitfenster\",\"alwaysRaised=yes,directories=no,hotkeys=no,location=no,resizable=no,screenX=0,screenY=0,status=no,titlebar=no,toolbar=no,width=500,height=200\");
</script>";