header already sent?

[deathemperor]

Originally Posted by arob42

I'm hacking the code and I am getting the following error message when I read a post:

Unable to add cookies, header already sent.
File: <new file that I added to forum/includes directory>
Line: 1

It lists a new php file that I am including in the functions_bbcodeparse.php via require_once(). I'm just trying to understand the code right now. Does anyone know what this error message means and what might cause it. The error message is displayed from around line 2466 in functions.php (search for 'cant_set_cookies'). Thanks.

the File: <new file that I added to forum/includes directory> may have a space before <?php, open it and remove that space.