Adsense when drupal page does not exist problem

Hello,

I have a problem using adsense on my drupal website.
Adsense works, but it also appears when I type in a path which doesn't exist.
I get a message then that the page does not exist (I do get the side bars and my menu),
but adsense does also show up (and if I am correct it is not allowed to have adsense on
pages with no content)

Also with search 404 pages I have the same problem. How can I make sure adsense does not
appear here? (the problem is, there is no url for this pages which I could put in the adsense module settings so I can
say that that specific url needs to be blocked out)