Please help me to fix this error this error
Warning: Cannot modify header information - headers already sent by (output started at /home/amberadv/public_html/admin/login.php:11) in /home/amberadv/public_html/admin/login.php on line 17
<?php
session_start();
include_once('connect.php');
if(isset($_REQUEST['login']))
{
$username=$_REQUEST['username'];
$password=$_REQUEST['password'];
$sql="select * from `admin` where `user`='$username' and `pass`='$password'";
$result=mysql_query($sql);
$records= mysql_fetch_array($result);
print_r($records);
//$count=mysql_num_rows($result);
$_SESSION['user']=$username;
if($records['user']==$username && $records['pass']==$password)
{
//echo "in";
header("Location:index.php");
}
else
{
echo "out";
print "Username And Password Incorrect";
}
}
?>