Problème lors du download de fichiers stockés

header("Content-Type: $content_type");
//header("Content-Description: File Transfer");
header('Content-Transfer-Encoding: binary');
header('Content-Length: ' . filesize($source));
header("Content-Disposition: attachment; filename=$name_file");


readfile($source);

<?php 
session_start();

$name_file = $_GET['name'];

require 'fonction.php';
include ("variables.inc");	
connexion();

$id = $_GET['id'];
$type_doc = $_GET['type'];

if(strcmp($type_doc, "tkt") == 0){
	$req = mysql_query($requete);
	$db_name = mysql_fetch_row($req);
}else if(strcmp($type_doc, "doc") == 0){
	$req = mysql_query($requete);
	$db_name = mysql_fetch_row($req);
}else if(strcmp($type_doc, "log") == 0){
	$req = mysql_query($requete);
	$db_name = mysql_fetch_row($req);
}else $db_name[0] = $file_log;

$source = str_ireplace("%2F", "/", $db_name[0]);

$content_type = mime_content_type($name_file);
if(!$content_type || strcmp($content_type, "") == 0) $content_type = "application/octet-stream";
header("Content-Type: $content_type");
//header("Content-Description: File Transfer");
header('Content-Transfer-Encoding: binary');
header('Content-Length: ' . filesize($source));
header("Content-Disposition: attachment; filename=$name_file");


readfile($source);

$conn = $_SESSION['type'];
if(strcmp($type_doc, "doc") == 0 || strcmp($type_doc, "log") == 0 || (strcmp($type_doc, "tkt") == 0 && strcmp($conn, "clt") == 0)){
	$date = date("d/m/Y H:i");
	$id_u = $_SESSION["id_user"];
	$req = mysql_query($requete2);
	while ($res = mysql_fetch_array($req)){
		$nom = decode($res["$Nom"])." ".decode($res["$Prenom"]);
	}
	if(strlen($nom) == 0 && strcmp($type_doc, "log") == 0) $nom = "Customer";
	else if(strlen($nom) == 0 && strcmp($type_doc, "doc") == 0 ) $nom = "Unknown";
	
	if(strcmp($type_doc, "log") == 0) $type = "Versions";
	else $type = "Documents";
	
	$text = "$date;$type;$name_file;$nom\n";
	$descriptor = fopen($file_log, "a+");				
	fwrite($descriptor, "$text");
	fclose($descriptor);
	flush();
}

?>