If you have unchecked Allow people to post comments on the article on the Options > Discussion panel, then you have only disabled comments on future posts. To completely disable comments, you will have to edit each past post and uncheck Allow Comments from the Write Post SubPanel. Alternatively, you could delete the wp-comments-post.php file, or run this MySQL query, from the command line on a shell account, or using phpMyAdmin: UPDATE wp_posts SET comment_status="closed";