"Cannot modify header information" Error

I was running into this problem when trying to view or download files:

Warning: Cannot modify header information – headers already sent by (output started at /home/public_html/wp-head.php:37) in /home/public_html/wp-content/plugins/wp-publication-archive/lib/class.wp-publication-archive.php on line 199

For those having the same issue, I was able to fix it by adding the following code to my functions.php file:

//allow redirection, even if my theme starts to send output to the browser
add_action('init', 'do_output_buffer');
function do_output_buffer() {
        ob_start();
}

For the full explanation of why this works, view this StackOverflow article here:

https://stackoverflow.com/questions/7381661/cannot-modify-header-information-headers-already-sent-by-wordpress-issue

Hope this saves someone else some trouble!

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