The forums will automatically set if a member hasn't read a thread using a red folder. Users are able to mark all forum threads as read with one simple click.
At the top right side of every forum there is a link to 'Mark Forum Read'. Clicking that link will remove all of the noted red folders next to each thread.
The unread folder is gone
There is also the ability to mark all the forums as read from the forum index page.
Click 'Mark Forum Read' for each forum to update.