Custom Press Error - "You are not allowed to edit this post."

I'm trying to set up a custom post type for adsense ads. I want to use it like includes on my pages and posts.

I have created the custom post for ads.
Then, I created the taxonomy for ads. And, I also created a Custom field.

When I enter my code into the text area of a new page I create under the ads taxonomy and click publish, I get the following error message > "You are not allowed to edit this post.".

I've looked through the settings area about a million times but can't seem to figure out what the problem could be.

Note: I'm logged in as the admin so it can't be that.

Any ideas?

Thanks!

Susanna