When you delete a discussion forum all of its topics and replies are deleted. If you want to preserve the topics and replies in a forum, but do not want other users to see them, you can assign the forum to a category with no target audience. You can also restrict administrator access by setting its permissions.
You can delete only the discussion forums for which you have unrestricted access permission. Administrators with unrestricted access to the Discussion Forums feature in System Roles (Manage Features > Community Manager Features) can delete forums.
To delete a discussion forum
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