Another post on this subject, i've looked for white space in the main files but all seems to be ok. I have one error when adding a shortcode in the functions file, but i've never had the error in the header before and we're months into coding the site.
Cannot modify header information - headers already sent by (output started at /var/www/vhosts/clienttestdomain.co.uk/httpdocs/wp-content/themes/kino/header.php:16) in /var/www/vhosts/clienttestdomain.co.uk/httpdocs/wp-includes/pluggable.php on line 754
it was when i added a function
if(wp_update_user(array('ID' => $currentUser->ID, 'user_pass' => $newpassword)))
in this function, if i swap this out for a return statement eg $output .= "hello world"; it is fine?
The second error is in an admin plugin, this didn't happen on my local server
Warning: Cannot modify header information - headers already sent by (output started at /var/www/vhosts/clienttestdomain.co.uk/httpdocs/wp-content/plugins/film_db/filmdb.php:81) in /var/www/vhosts/clienttestdomain.co.uk/httpdocs/wp-includes/pluggable.php on line 934
I've checked the code and it still all works fine just shows this error, here is the method of the object that contains the code with line 81
I don't know where to start, what does this error even mean, what headers sent? Any help would be gladely received, i'm a broken man!!!