PHP readfile() causing corrupt file downloads

Question

I am using php script to provide download from my website after a requisite javascript timer this php script is included which causes the download. But the downloaded file i

Answer 1

This helped me in case of more output buffers was opened.

//NOW comes the action, this statement would say that WHATEVER output given by the script is given in form of an octet-stream, or else to make it easy an application or downloadable
header('Content-type: application/octet-stream');
header('Content-Length: ' . filesize($f));
//This would be the one to rename the file
header('Content-Disposition: attachment; filename='.$n.'');
//clean all levels of output buffering
while (ob_get_level()) {
    ob_end_clean();
}
readfile($f);
exit();