Codeigniter - Cannot modify header information - h

Question

A PHP Error was encountered
Severity: Warning

Message: Cannot modify header information - headers already sent by (output started at /home/aphotel/public_html/application/config/config.php:1)

Filename: libraries/Session.php

Line Number: 366

#

Weird part of it, there is no session.php file in libraries folder

Answer 1

I had this problem before and it was caused by output_buffering was Off.

Edit your php.ini and search for output_buffering and make it looks like this

output_buffering = On

Answer 2

Make sure you do not have any white space characters before the opening php tag in your controller class.

Answer 3

There seems to be whitespace before the php open tag

Answer 4

In PHP Use " ob_start(); " at first line and in CI controller constructor at first line " ob_start(); " //output buffer

Answer 5

There is space before the <?php tag in the below file. I have seen this issue multiple times.

(output started at /home/aphotel/public_html/application/config/config.php:1)

Answer 6

Just load session library first.

$autoload['libraries'] = array('session', 'encrypt', 'database',...