无法修改标题信息 - 处理页面时已经发送的标题[重复]

Question

This question already has an answer here:

• How to fix “Headers already sent” error in PHP 11 answers

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";

    }

}

?> 

</div>

Answer 1

Problem is you are echo something before you do header("Location:index.php"); redirection

Check these cases

• Remove the space before <?php tag
• Remove all echo statements in connect.php and login.php