Upgraded our forum software today to » YaBB 2.2.1 (released March 5th). This version fixes all the problems associated with the not-yet-ready-for-primetime YaBB 2.2 release (Nov 2007).
I use the term "upgrade," but it's actually more accurate to call it a "fresh/clean installation" of YaBB 2.2.1, followed by importing all the Members and Messages from the old Y2.2 forum.
Last time I did this (on January 22nd) it was a disaster .. as the file-transfer (from old to new directories) choked, and we lost over half our members and 3/4'ers of our posts. I stayed up 'til 4:30, and spent the whole next day restoring files from a back-up.
This time however, everything went without a hitch. I asked the techs who run our new VPS server what they thought would be the best way to transfer such a large number of files (~10,000).
They suggested I log into the root/shell access (using PuTTy) and use the Linux "copy" command from the command line.
It went so freaking fast that I thought something was wrong. But when I looked, all our members, and their posts were there, all accounted for. Boy, was I stoked!