Back in 2010, running vB, I sent out a mass message to all of our members, 500 at a time. We've since converted to XF (obviously). A member who hasn't been on since then just replied to the message, sending the replies to the 498 other members that I had originally sent the message. My guess is this will probably have to be something done on the back end, but I need to delete this conversation. How can I do so?