WordPress total posts per page changed and now 404 Http error comes out [closed]

Question

I have migrate my web site from Joomla to WordPress. All are fine, I have create my Rewrites in htaccess to stop 404 from old URLs but I have problem with pagination.

In Joomla web site, I had 6 posts per page, but now in WordPress I need to display 10 posts per page. That's fine too.

The problem is that, in WordPress site now the very very last pages return 404 error because of the 10 posts per page I use now.

i.e.: In Joomla to get the 60th article I had to go on page 10, but now page 10 does not exists anymore, because In WordPress the very very last page now is the page 6. In that case, I will try to access the 7th, 8th, 9th or 10th page I get a 404 HTTP Error.

How can I fix that?

Answer 1

The only way to really know if it's going to be a 404 is to let WordPress try to load it and check results before WP sends headers.

If you put this in your functions.php (not on a live site! use a dev mirror.), then visit a page that throws a 404, you can see the contents of the $wp_query object produced, is_404 will be true. By inspecting this you can determine what you want to do.

add_filter('template_redirect', 'wpse25745_inspect_query' );
function wpse25745_inspect_query() {
    global $wp_query;

    echo '<pre>';
    print_r($wp_query);
    echo '</pre>';
    die();

}

Following on that, you can redirect somewhere like this:

add_filter('template_redirect', 'wpse25745_inspect_query' );
function wpse25745_inspect_query() {
    global $wp_query;

    if( $wp_query->is_404 && $some_other_conditions_met == 'foo' ):
        wp_redirect( home_url(),301 );
        exit;
    endif;
}