$_SESSION variable isn't sending data to next page

Question

I am working on a php script that sends data over to next page after a successful log in.

I got it to work 100% on my localhost.

But now that I uploaded to a server, the variable isn't being passed over anymore. Furthermore, I had to make changes to my PHP script because it wouldn't execute header("Location: blah.php).

After some research I found that ob_start() fixed the problem with the header.

I"m wondering if that is what caused my $_SESSION to not send data over to the next page.

Here is the code for the first page:

if (mysqli_num_rows($result) == 1){
    $_SESSION['currentUser'] = $username;
    header("Location: loggedin.php"); 

And this is the second page where I get the session variable currentUser.

//start the session
session_start();
//grab the current user
$currentUser = $_SESSION['currentUser'];
echo "You're Logged in as: ". $currentUser;

When i run the script, it only prints out You're Logged in as: with no username.

Answer 1

Call session_start() on the first page.