Ciao , mi aiutate? Sono una frana...
Io ho una pagina per il login:

codice:
<html>
<head>
<title>Maschera Login</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<link rel="stylesheet" type="text/css" href="stile.css"></head>
<body>

<div id="container">

    <div id="header">
    [img]images/LogoFotografando.jpg[/img]
    <h1>Museo della fotografia italiana</h1>
    Lucca, Complesso monumentale di San Micheletto 
    </div>
    
       <div id="navigation">
          Home  |  
          Informazioni  |  
          Eventi  |  
          Collezione  |  
          Login  | 
          Registrati
       </div>
       
  <div id="content">
    
             <div id="right">
             [img]images/foto1.jpg[/img]

             <font size="1" face="arial">Chiostro: angolo di nord-ovest.</font>


             [img]images/foto2.jpg[/img]

             <font size="1" face="arial">Veduta aerea del Complesso 
Monumentale di San Micheletto</font> 
             </div>
    

	    <h2>Effettua il login al sistema</h2>


        

Immetti nei campi specifici i tuoi dati:</p>

<?php 

// Connects to your Database 
mysql_connect("127.0.0.1", "root", "") or die(mysql_error()); 
mysql_select_db("museo2") or die(mysql_error()); 

//Checks if there is a login cookie
if(isset($_COOKIE['ID_my_site']))

//if there is, it logs you in and directes you to the members page
{ 
$username = $_COOKIE['ID_my_site']; 
$pass = $_COOKIE['Key_my_site'];
$check = mysql_query("SELECT * FROM utenti WHERE username = '$username'")or die(mysql_error());
while($info = mysql_fetch_array( $check )) 
{
if ($pass != $info['password']) 
{
}
else
{	 
header("Location: members.php");
}
}
}

//if the login form is submitted
if (isset($_POST['submit'])) { // if form has been submitted

// makes sure they filled it in
if(!$_POST['username'] | !$_POST['pass']) {
die('You did not fill in a required field.');
}
// checks it against the database
$check = mysql_query("SELECT * FROM utenti WHERE username = '".$_POST['username']."'")or die(mysql_error());

//Gives error if user dosen't exist
$check2 = mysql_num_rows($check);
if ($check2 == 0) {
die('That user does not exist in our database. <a href=registrazione.php>Click Here to Register</a>');
}
while($info = mysql_fetch_array( $check )) 
{
$_POST['pass'] = stripslashes($_POST['pass']);
$info['password'] = stripslashes($info['password']);
$_POST['pass'] = md5($_POST['pass']);

//gives error if the password is wrong
if ($_POST['pass'] != $info['password']) {
die('Incorrect password, please try again.');
}
else 
{ 

// if login is ok then we add a cookie 
$_POST['username'] = stripslashes($_POST['username']); 
$hour = time() + 3600; 
setcookie('ID_my_site', $_POST['username'], $hour); 
setcookie('Key_my_site', $_POST['pass'], $hour); 

//then redirect them to the members area 
header("Location: members.php");

} 
} 
} 
else 
{ 

// if they are not logged in 
?> 
<form action="<?php echo $_SERVER['PHP_SELF']?>" method="post"> 
<table border="0"> 
<tr><td colspan=2><h1>Login</h1></td></tr> 
<tr><td>Username:</td><td> 
<input type="text" name="username" maxlength="40"> 
</td></tr> 
<tr><td>Password:</td><td> 
<input type="password" name="pass" maxlength="50"> 
</td></tr> 
<tr><td colspan="2" align="right"> 
<input type="submit" name="submit" value="Login"> 
</td></tr> 
</table> 
</form> 
<?php 
} 
?> 
    </div> 
          <div id="footer">© 2007 - Sito Web realizzato da xxx</div>
</div>
</body>
</html>
Mi rilascia questi errori (le righe le ho evidenziate in grassetto):

Warning: Cannot modify header information - headers already sent by (output started at c:\programmi\easyphp1-8\www\museo2\mascheralogin.php:13) in c:\programmi\easyphp1-8\www\museo2\mascheralogin.php on line 59

Warning: Cannot modify header information - headers already sent by (output started at c:\programmi\easyphp1-8\www\museo2\mascheralogin.php:13) in c:\programmi\easyphp1-8\www\museo2\mascheralogin.php on line 95

Warning: Cannot modify header information - headers already sent by (output started at c:\programmi\easyphp1-8\www\museo2\mascheralogin.php:13) in c:\programmi\easyphp1-8\www\museo2\mascheralogin.php on line 96

Warning: Cannot modify header information - headers already sent by (output started at c:\programmi\easyphp1-8\www\museo2\mascheralogin.php:13) in c:\programmi\easyphp1-8\www\museo2\mascheralogin.php on line 101

Come dovrei fare per risolvere? So che il problema è dovuto al fatto che headers e cookie non richiedono nessun tipo di output davanti, ma come faccio allora? :master:

Grazie!