Wordpress help

Hi,

My blog is up and running again.
But I have some problems in the admin area.
When I try to add/delete categories/post/comments I get a error message where it says " You dont have permission to do that "

Ive been using WP for over a year - but never seen this error message before.

Does anyone know the trick so I can fix this "problem" ?

Thanks for all the help!

- kenny