echo "<script type='text/javascript'>
window.location.href='file://C:/DescMan/abc.html';</script>";

header('Location: file://C:/DescMan/abc.html');

header('Content-Disposition: filename="abc.html"');readfile("C:/DescMan/abc.html");

echo "<meta http-equiv='refresh' content='0'; url='C:/DescMan/abc.html'/>";