Often times a new user will come to the site due to a search engine, and will end up replying to a thread that is several months (if not years) old. This generally leads to a mod having to move the post, or other users chastising them. However, locking old threads altogether isn't necessarily the right thing either, because in some cases it could very well take months before someone else replies, depending on the subject matter. To that end, I'd hate to lose the possibility of someone finally coming around to answer an old question. So to me, the best mixture of the two is auto moderation. In my dream scenario it works as such: Admin.php Options You select how many Days before a thread is considered old and "locked for moderation" (based on the latest post in the thread) (optional) you select which forums should/shouldn't be affected by this add-on User view User comes to a thread that is older than the threshold and sees the normal reply to box at the bottom, however it also contains a warning that this thread is old and any new replies must be approved, etc. Then the post simply goes into the mod queue and awaits approval or denial. There is already an add-on that is similar to this, but lacks the ability to auto moderate the post. I did some very cursory research and didn't see any changes to the rendered html on a thread that was open for posts vs requires moderation, which leads me to believe it's a somewhat more complicated feature than one would hope. Because of that I am posting this request here, rather than trying to burden the author with something he might not be interested in pursuing. http://xenforo.com/community/thread...e-user-to-tick-to-reply-to-old-threads.12019/ If you are unsure of what I mean I'd happily mock up some screenshots, but I think the ones shown in RickM's addon are close enough for you to get the idea.