Untitled

<html>
<head>
    <title>
        <?php
            session_start();
        ?>
    </title>
</head>
<body>
    <?php

        $connection = mysql_connect("localhost", "root", "root");
        if(!connection)
        {
            die("could not connect to the database");
        }
        mysql_selectdb("phplogin", $connection) or die ("MySQL error i valg af database: " .mysql_error());
        $query = "Select * from users where username='".$_POST['username']."' AND password = '".$_POST['userpass']."'";
        $result = mysql_query($query);
        $count = mysql_num_rows($result);
        if($count==1){
            $_SESSION['loggedIn'] = "true";
            echo "The variable: ".$_SESSION['loggedIn'];
            header("Location: loggedinPage.php");
            exit;
        }
        if(!$count == 1){
            header("Location:Login.php");
            exit;
        }
    ?>
</body>

<html>
<head>
    <title>
        <?php
            session_start();
        ?>
    </title>
</head>
<body>
    <?php
        if($_SESSION['loggedIn'] != "true"){
            echo "You are NOT logged in";
            echo $_SESSION['loggedIn'];
            exit;
        }
            echo $_SESSION['loggedIn'];
            echo "You are logged in";
    ?>
</body>

<?php
    session_start();
    ?>
    <?php

        $connection = mysql_connect("localhost", "root", "root");
        if(!connection)
        {
            die();
        }
        mysql_selectdb("phplogin", $connection) or die ("MySQL error i valg af database: " .mysql_error());
        $query = "Select * from users where username='".$_POST['username']."' AND password = '".$_POST['userpass']."'";
        $result = mysql_query($query);
        $count = mysql_num_rows($result);
        if($count==1){
            $_SESSION['loggedIn'] = "true";
            header("Location: loggedinPage.php");
        }
        if(!$count == 1){
            header("Location:Login.php");
        }
    ?>

<head>
    <title>

    </title>
</head>
<body>

</body>

<html>
...

$_SESSION['loggedIn'] = "true";

if($_SESSION['loggedIn'] != "true"){ ...

if(!isset($_SESSION['loggedIn']) || $_SESSION['loggedIn'] != "true"){ ...