I am newbie for mpdf so don\'t mind if you feel this question is stupid one:),
I generated the pdf document usinf mPDF class , the issue is that after pdf generated
Add 'D' parameter for download
$mpdf->Output('MyPDF.pdf', 'D');
for downloading use this
$filename = "mpdf.pdf"; if (file_exists($filename)) { header('Content-type: application/force-download'); header('Content-Disposition: attachment; filename='.$filename); readfile($filename); }