Problema login utenti (non rimangono connessi)

Salve,non capisco perchè gli utenti non rimangono connessi quando cambiano pagina...
Ecco il codice del file login.php:

Codice HTML:

<?php 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"); $err[] = "Account not activated. Please check your email for activation code"; // ("Location: login.php?msg=$msg"); //exit(); } //check against salt if ($pwd === PwdHash($pass,substr($pwd,0,9))) { if(empty($err)){ // 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",$_SESSION['user_name'], time()+60*60*24*COOKIE_TIME_OUT, "/"); } header("Location: Homepage.php"); } } else { //$msg = urlencode("Invalid Login. Please try again with correct user email and password. "); $err[] = "Login Invalido. Riprova con email e password corretti."; //header("Location: login.php?msg=$msg"); } } else { $err[] = "Errore - Login Invalido. Utente Inesistente"; } } ?> <html> <head> <title>Login Utenti</title> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> <script language="JavaScript" type="text/javascript" src="js/jquery-1.3.2.min.js"></script> <script language="JavaScript" type="text/javascript" src="js/jquery.validate.js"></script> <script> $(document).ready(function(){ $("#logForm").validate(); }); </script> <link href="styles.css" rel="stylesheet" type="text/css"> </head> <body> <a href="http://forum.it.altervista.org/../Homepage.htm" title="Farebury"><img src="http://forum.it.altervista.org/../immagini/logo.png" alt="Farebury" style="border: 0px none" align="left" height="82" width="744" /></a><br><br> <table width="100%" border="0" cellspacing="0" cellpadding="5" class="main"> <tr> <td colspan="3"> </td> </tr> <tr> <td width="160" valign="top"><p> </p> <p>  </p> <p> </p> <p> </p> <p> </p></td> <td width="732" valign="top"><p> </p> <h3 class="titlehdr">Login Utenti </h3> <p> <?php /******************** ERROR MESSAGES************************************************* This code is to show error messages **************************************************************************/ if(!empty($err)) { echo "<div class=\"msg\">"; foreach ($err as $e) { echo "$e <br>"; } echo "</div>"; } /******************************* END ********************************/ ?></p> <form action="login.php" method="post" name="logForm" id="logForm" > <table width="65%" border="0" cellpadding="4" cellspacing="4" class="loginform"> <tr> <td colspan="2"> </td> </tr> <tr> <td width="28%">Username / Email</td> <td width="72%"><input name="usr_email" type="text" class="required" id="txtbox" size="25"></td> </tr> <tr> <td>Password</td> <td><input name="pwd" type="password" class="required password" id="txtbox" size="25"></td> </tr> <tr> <td colspan="2"><div align="center"> <input name="remember" type="checkbox" id="remember" value="1"> Ricordami</div></td> </tr> <tr> <td colspan="2"> <div align="center"> <p> <input name="doLogin" type="submit" id="doLogin3" value="Login"> </p> <p><a href="register.php">Registrati</a><font color="#FF6600"> |</font> <a href="forgot.php">Password Dimenticata</a> <font color="#FF6600"> </font></p>  </div></td> </tr> </table> <div align="center"></div> <p align="center">  </p> </form> <p> </p> </td> <td width="196" valign="top"> </td> </tr> <tr> <td colspan="3"> </td> </tr> </table> </body> </html>

E questa la Homepage.php

Codice HTML:

<html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Farebury</title> <link rel="icon" href="../../favicon.ico" /> </head> <body>  <table width='75%'> <tr> <td><a href="http://forum.it.altervista.org/../Homepage.htm" title="Farebury"><img src="http://forum.it.altervista.org/../immagini/logo.png" alt="Farebury" style="border: 0px none" align="left" height="82" width="744" /></a></td> <form action="login.php" method="post" name="logForm" id="logForm" > <td width="28%">Username / Email</td> <td width="50%"><input name="usr_email" type="text" class="required" id="txtbox" size="25"></td> <td>Password</td> <td><input name="pwd" type="password" class="required password" id="txtbox" size="25"></td> <td><input name="doLogin" type="submit" id="doLogin3" value="Login"></td> <td width='80'><input name="remember" type="checkbox" id="remember" value="1" width='100'>Ricordami</td> </form> <td><a href="register.php">Registrati</a><font color="#FF6600"> <font color="#FF6600"> |</font> <a href="forgot.php">Password Dimenticata</a> <font color="#FF6600"></td> </tr> </table> </body> </html>

Qualcuno riesce ad aiutarmi?