Permission Problems

I'm having serious problems with permissions.

I've set my Download perm. for the group Public and Registered to "Allowed" , my Category to Public, and my documents to "Registered".

At first, it works as expected, registered users can view and download docs.

Today, without modify anything, it stopped working.

If you try to see or download any document, it says "Invalid category, or you are not allowed to see this Category"

All Categories are Public. I have also tryed to set a document to Public, so all the perms. are setted toPublic, and the same error appears.

Whats wrong ?

That's strange. Could you please submit a support ticket sending us administrator and FTP account of your site so that I can check and solve it for you ?

Tuan