Forums / Cotonti / Support / private Posts for one lowered group User

Yes you can set it so that one group can vire a topic and the other cant.

Alright lets say that you have 2 forum topics.

Private forum (which you intend only for admins and mods)
Public offtopic forum (which you intend for everybody)

Go to Administration > Forums (The tab)
Now look for the topics. All the way to the right is says "Rights"

Rights are what allows or denies users to certain parts of the site.

If you want only Admins and Mods. Then place a check next to the rank for the groups you want to allow to use that forum. If you want someone to not use that section. Then uncheck the box.

Click ok and it should be done.

Remember their are 3 sections. 1 section is so that users can only see the the topic. Another section is they can write new topics. Another section is where they can administrate (should be left only for mods).