problem updrading to 3.8.4
 

i have installed the 3.8.3 version and when i tried to upgrade to the latest version 3.8.4
i got the following error
Warning: Cannot modify header information - headers already sent by (output started at /home/kootta/public_html/upload/includes/config.php:1) in /home/kootta/public_html/upload/includes/functions.php on line 3103
so what's the problem
thanks