Php error : "Cannot modify header information"

Issue :

Are you familiar with the following PHP error. ?

[Warning: Cannot modify header information – headers already sent by (output
started at /home/jusdor/public_html/forum/config.php:48) in
/home/jusdor/public_html/forum/addtopic.php on line 72]

Fix :

Edit php.ini and set

output_buffering = on;

Output buffering allows you to send header lines (including cookies) even after you send the body content, at the cost of slowing PHP’s output layer a bit.