Session perdu après la page de redirection en php

Lorsque j'utilise php header de redirection de toutes les variables de session sont perdues... Certaines personnes disent que l'ajout de exit(); juste après l'en-tête(""); permettra de résoudre le problème, mais il ne semble pas être la solution...

Quelqu'un peut s'il vous plaît aider?

Voici comment j'magasin variable dans la session:

include 'dbc.php';
$err = array();
foreach($_GET as $key => $value) {
$get[$key] = filter($value); //get variables are filtered.
}
if ($_POST['doLogin']=='Login')
{
foreach($_POST as $key => $value) {
$data[$key] = filter($value); //post variables are filtered
}
$user_email = $data['usr_email'];
$pass = $data['pwd'];
if (strpos($user_email,'@') === false) {
$user_cond = "user_name='$user_email'";
} else {
$user_cond = "user_email='$user_email'";
}
$result = mysql_query("SELECT `id`,`pwd`,`full_name`,`approved`,`user_level` FROM users WHERE 
$user_cond
AND `banned` = '0'
") or die (mysql_error()); 
$num = mysql_num_rows($result);
//Match row found with more than 1 results  - the user is authenticated. 
if ( $num > 0 ) { 
list($id,$pwd,$full_name,$approved,$user_level) = mysql_fetch_row($result);
if(!$approved) {
//$msg = urlencode("Account not activated. Please check your email for activation code");
$err[] = "Account not activated. Please check your email for activation code";
//header("Location: login.php?msg=$msg");
//exit();
}
//check against salt
if ($pwd === PwdHash($pass,substr($pwd,0,9))) { 
//this sets session and logs user in  
session_start();
session_regenerate_id (true); //prevent against session fixation attacks.
//this sets variables in the session 
$_SESSION['user_id']= $id;  
$_SESSION['user_name'] = $full_name;
$_SESSION['user_level'] = $user_level;
$_SESSION['HTTP_USER_AGENT'] = md5($_SERVER['HTTP_USER_AGENT']);
//update the timestamp and key for cookie
$stamp = time();
$ckey = GenKey();
mysql_query("update users set `ctime`='$stamp', `ckey` = '$ckey' where id='$id'") or die(mysql_error());
//set a cookie 
if(isset($_POST['remember'])){
setcookie("user_id", $_SESSION['user_id'], time()+60*60*24*COOKIE_TIME_OUT, "/");
setcookie("user_key", sha1($ckey), time()+60*60*24*COOKIE_TIME_OUT, "/");
setcookie("user_name",$_SESSION['user_name'], time()+60*60*24*COOKIE_TIME_OUT, "/");
}
if(empty($err)){            
header("Location: myaccount.php");
}
}
else
{
//$msg = urlencode("Invalid Login. Please try again with correct user email and password. ");
$err[] = "Invalid Login. Please try again with correct user email and password.";
//header("Location: login.php?msg=$msg");
}
} else {
$err[] = "Error - Invalid login. No such user exists";
}     
}

Redirection code:

//connect database
require_once 'dbc.php';
page_protect();
$authorID = $_SESSION['user_id'];
if ( !empty($_POST["answ_content"]) && $authorID != 0 ) {
//vaqciot html chveulebriv texad
$content = htmlentities($_POST["answ_content"],ENT_COMPAT,'UTF-8');
$dro = date('Y-m-d H:i:s');
$qID = $_POST["question_ID"];
$author = $_SESSION["user_name"];
$sql="INSERT INTO wp_comments (comment_ID, comment_post_ID, comment_author, comment_author_IP, comment_date, comment_content, user_id) 
VALUES
(NULL, '$qID', '$author', '123.123.123.123', '$dro', '$content', '$authorID')";
$result = mysql_query($sql);
//pasuxebis raodenobis ertit gazrda
$increase = "UPDATE wp_posts SET comment_count = comment_count+1 WHERE ID = $qID";
mysql_query($increase);
//gadamisamarteba shekitxvis gverdze  
$url = 'Location:http://example.com/site/answ/question.php?ID=' .$qID;
header($url);
} else {
echo 'error';
}

OriginalL'auteur King Julien | 2010-06-11