PHP $_SESSION data returning empty - php

Question

I have a login.php file:
<?php
session_start();
include('db.php');
if(isset($_POST['email']) && !empty($_POST['email']) AND isset($_POST['password']) && !empty($_POST['password'])){
$email = mysql_escape_string($_POST['email']);
$password = mysql_escape_string($_POST['password']);
$search = mysql_query("SELECT * FROM users WHERE email='".$email."' AND password='".$password."' AND active='1'") or die(mysql_error());
$match = mysql_num_rows($search);
if($match > 0){
$row = mysql_fetch_assoc($search);
$user=$row['forename'].' '.$row['surname'];
$_SESSION['username']=$user;
//$msg = 'Login Complete! Thanks, '.$user.'!';
header( 'Location: page1.php' ) ;
die;
}else{
$msg = 'Login Failed!<br /> Please make sure that you enter the correct details and that you have activated your account.';
}
}
?>
Now, when I load page1.php I have issues. The file contains this...
<?php
session_start();
include('db.php');
if(isset($_SESSION['username'])){
echo 'Success, '.$_SESSION['username'].'!';
}else{
echo 'No dice!';
//header( 'Location: login.php' ) ;
}
?>
I ideally want it to redirect to login if there isn't a username stored. If there is, I want to allow them to view. However, I am getting "No dice!" every time, so it looks like I am not retrieving (or storing) the data correctly. What am I doing wrong?
To be clear, the else shouldn't be firing as it should be referring to session data set in index.php. The redirection is not a problem.
The problem was specific to my host who had a strange setup. On contacting them, they provided me the correct path information which I had to use session_save_path to set. Awarded the right answer on this basis.

Answer 1

Redirect is malformed. You have to specify full url, like this:
header('Location: http://your.site.com/page1.php');
die;
It's important to end the script after redirect.
If session data is not preserved, maybe you have some configuration issues. Verify your php configuration and check write permissions where session data is stored.
<?php phpinfo();?>

Answer 2

I would comment this but the under 50 rep limit means I can't for some reason. Try
$row = mysql_fetch_assoc($search);
$user=$row['forename'].' '.$row['surname'];
echo 'User: '.$user.'<br />';
$_SESSION['username']=$user;
echo 'Session: '.$_SESSION['username'];
//header( 'Location: page1.php' ) ;
and see if anything is actually being stored in the varibles.
EDIT: Try this
if($match > 0){
$row = mysql_fetch_assoc($search);
$user=$row['forename'].' '.$row['surname'];
$_SESSION['username']=$user;
$_SESSION['logintrue'] = true;
//$msg = 'Login Complete! Thanks, '.$user.'!';
header( 'Location: page1.php' ) ;
die;
}
session.php
<?php
session_start();
if(!$_SESSION['logintrue'])
{
header( 'Location: login.php' ) ;
}
$SessionUsername = $_SESSION['username'];
?>
page1.php
<?php
require_once 'session.php';
require_once 'db.php';
echo 'I work now maybe?<br />';
echo $SessionUsername;
?>
Also includes aren't functions so write them like include 'db.php'; I've made that mistake aswell.