Forum Moderators: coopster
My .htaccess file is completely empty
No it is not :) Wordpress adds a line which maps all 404 pages to index.php. A request for www.example.com/blog/some-post/ generates a 404 Not found and the webserver executes Wordpress index.php to display an error message. When index.php is invoked, Wordpress interprets the URL and generates the requested page with a new 200 header.