This approach should solve the problems mentioned here
download.php?filename=test.xlsx
if isset ($_GET['filename']){
$filename = $_GET['filename']
}
else{
die();
}
header('Content-Description: File Transfer');
header('Content-Type: application/octet-stream');
header('Content-Disposition: attachment; filename='.basename($file));
header('Content-Transfer-Encoding: binary');
header('Expires: 0');
header('Cache-Control: must-revalidate');
header('Pragma: public');
header('Content-Length: ' . filesize($file));
ob_clean();
flush();
readfile($file);
And of course don't forget to secure this so users can't download other files