You can display your original “404 File Not Found”.

1. Open “_dot_htaccess” file in your P_BLOG’s home directory with your favorite text editor and find the line :

# ErrorDocument 404 http://www.example.com/your/p_blog/var/index.php?id=error404

2. Delete “#”, and edit like this.

ErrorDocument 404 http://your/path/to/p_blog/var/index.php?id=error404

3. Lastly, save the changes and rename “_dot_htaccess” to “.htaccess”.

… Done! Hit URI which doesn’t exist and see if it works.

Custom messages are in 「/var/contents/」. You can use custom “401” and “403” as well.