It does not work from the start

Ok, let’s try some so simple as just using the shortcode [php] [/php] in the content of a page/post.

So,,,, OK
WP_admin > Pages > Add New got to “content box (Visual or Text)

add code “[php] [/php]” without ” & “.

activate/click “Update” button
load in browser

error. yeaaa, same error

http://wordpress.org/plugins/allow-php-in-posts-and-pages/