Error: Please select a category

Hi

I use CuteNews since a long time ago and for a lot of sites. I could fix things but this error is the first time I got and I can´t understand why. When I try to EDIT an article (delete and new, no problem), I have this error:

"Error !!!
   
Please select a category.

go back"

(of course, I select a category).

I checked all permissions and nothing. This starts when I created a new category (until now its works fine) and starts doing this (in old and new articles). Also checked the quote.

What`s the problem?