Board Permissions

[ColdXX]

How do i stop a certain membergroup to post on a specific board?

[Chalky]

Admin > Forum > Boards.  Click Modify next to the board you want and uncheck the relevant membergroup if you don't want them to access it at all.

If you want the specified membergroup to see but not post, go to the same place only click on "Permissions set" under "Permissions profile".  Create a new set of permissions in which your selected membergroup cannot post and choose that created permissions profile for your board.