Removing forum permission based on usergroup
 

Hi*

how do I REMOVE a forum permission* based on a usergroup?

Here's what I would like to achieve:

I have 4 main forums* totally unrelated to each other. Some users do not want to see one (or more) of these forums. I would like to create a usergroup that they can join* and when they do* not be able to access (not even see) one of these 4 forums.

So originally: forum A* B* C* D. New usergroup: "I do not want to see forum C". People who join this usergroup* will only have access to forums A* B and D from then on.

How can I do this?

Thanks*

Attila