MyBB Community Forums

i moved my old 1.6.10 mybb forum to my desktop for backup, then deleted/installed a new 1.6.10 on my server for a fresh copy. from the old forum files in my desktop, what folders do i paste to add the old threads to the new forum?

see replies at http://community.mybb.com/thread-89481.html
and http://community.mybb.com/thread-141710.html
(there are more similar threads with guidance & youtube videos also exist)