I do not know why you are getting the "locked" thing, I can reply to everything and anything. Can you advise at how it is "locked" as you put it? There is also the Reply to Topic link at the top and the bottom of all messages.
working at two diff computers the 1 at work does e.thing home 1 is the one with problem.do not understand why? the messabe comes up on screen as "you have replied to a locked topic"press "back" to respond???