Please see php script below. When I log in, the screen goes blank and on the same /login.php web page. If I enter a wrong password, it will tell me it is wrong, and I registered and activated the user/password successfully. It is just when I login in, it doesn't redirect to index.php (with an open session). It just goes blank. Please help!

<?php # Script 16.8 - login.php
// This is the login page for the site.

require_once ('includes/');
$page_title = 'Login';
include ('includes/header.html');

if (isset($_POST['submitted'])) {
require_once (MYSQL);

// Validate the email address:
if (!empty($_POST['email'])) {
$e = mysqli_real_escape_string($dbc, $_POST['email']);
} else {
$e = FALSE;
echo '<p class="error">You forgot to enter your email address!</p>';

// Validate the password:
if (!empty($_POST['pass'])) {
 $p = mysqli_real_escape_string ($dbc, $_POST['pass']);
 } else {
 $p = FALSE;
 echo '<p class="error">You forgot to enter your password!</p>';

if ($e && $p) { // If everything's OK.

// Query the database:

$q = "SELECT user_id, first_name, user_level FROM users WHERE (email='$e' AND pass=SHA1('$p'))AND active IS NULL";
$r = mysqli_query ($dbc, $q) or trigger_error("Query: $q\n<br />MySQL Error: " . mysqli_error($dbc));

if (@mysqli_num_rows($r) == 1) { // A match was made.

// Register the values & redirect:
$_SESSION = mysqli_fetch_array($r, MYSQLI_ASSOC);

$url = BASE_URL . 'index.php'; // Define the URL:
ob_end_clean(); // Delete the buffer.
header("Location: $url");
exit(); // Quit the script.

} else { // No match was made.
echo '<p class="error">Either the email address and password entered do not match those on file or you have not yet activated your account.</p>';

} else { // If everything wasn't OK.
echo '<p class="error">Please try again.</p>';


} // End of SUBMIT conditional.

<p>Your browser must allow cookies in order to log in.</p>
<form action="login.php" method="post">
<p><b>Email Address:</b> <input type="text" name="email" size="20" maxlength="40" /></p>
<p><b>Password:</b> <input type= "password" name="pass" size="20" maxlength="20" /></p>
<div align="center"><input type="submit" name="submit" value="Login" /></div>
<input type="hidden" name="submitted" value="TRUE" />

<?php // Include the HTML footer.
include ('includes/footer.html');

GoDaddy is hosting my website. And I heard the they have problems dealing with active seeions $_Sessions(). Is this is true? Can this be my problem?