Whatever things you do on lines 29, 30, and 32 are trying to modify headers. This could be due to a number of things, including the header() function as well as things like session_start() and setcookie(). Any such function will not work if any output has already been sent to the user, including any text (even white-space) not within <?php...?> tags.
This problem is being encountered because of something at line 34 of the host.config.inc.php file, which apparently is included by the main script before the problematic header-setting lines. In addition to explicit outputs in such an include file, a common cause of this is white-space (including newlines) before the <?php tag at the start of the include file or after the ?> tag. I've developed the habit of simply leaving out the final ?> tag in included files to avoid the latter issue, as the PHP parser will assume it is there when it gets to the end.
