i have header.php that include nav bar with using the session to transfer stored data but the problem is that the browser keep display the error message:
A session had already been started - ignoring session_start() in C:\wamp\www\new adamKhoury\header.php on line 2
header.php
<?php
session_start();
ob_start();
/*if($_SESSION['login'] != 'true'){
header("location:index.php");
}*/
//var_dump($login_user);
require_once('include/connect.php');
$id = ($_SESSION['user_id']);
$username= ($_SESSION['user_name']) ;
var_dump($username);
var_dump($id);
?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Untitled Document</title>
<link href='http://fonts.googleapis.com/css?family=Oswald:400,300' rel='stylesheet' type='text/css' />
<link href='http://fonts.googleapis.com/css?family=Abel|Satisfy' rel='stylesheet' type='text/css' />
<link href="default.css" rel="stylesheet" type="text/css" media="all" />
</head>
<body>
<div id="banner">
<div class="img-border">
<div id="header-wrapper">
<div id="header">
<div id="logo">
<marquee width="80%">
<h1><b>Social Media Network</b></h1>
</marquee>
</div>
<div id="menu">
<ul>
<li><a href="profile.php" accesskey="1" title=""><?php echo $username ?>'s Profile</a></li>
<li><a href="update_account.php" accesskey="2" title="">Update</a></li>
<li><a href="search.php" accesskey="3" title="">Search</a></li>
<li><a href="map.php" accesskey="4" title="">Map</a></li>
<li><a href="feedback_form.php" accesskey="4" title="">Feedback</a></li>
<li><a href="help.php" accesskey="6" title="">Help</a></li>
<li><a href="logout.php" accesskey="7" title="">Logout</a></li>
</ul>
</div>
</div>
</div>
<img src="images/web_header copy.jpg" width="1121" height="210" alt="" />
</div>
</div>
</body>
</html>
<?php ob_end_flush(); ?>