PHP Error "Cannot modify header information" - headers already sent by

Question

This error is coming when I am trying to run my php script

 

Warning: Cannot modify header information - headers already sent by (var/home/www/html/project /src/run.php:13) in src/run.php on line 33

 

And these lines 13 and 33 contains header() and setcookie() function.

 

can you please tell me the solution and reason as well as.

 

Answer 1

Quick fix is to wrap the code with ob_start(). Error means that you are prematurely sending output to the browser

Answer 2

remove the white spaces in your file after the php closing tag i.e ?>, php tags must be close properly ,  or you can remove the php closing tag and remain it open server will close it by itself.