The "closed" letter isn't a letter, but a command reply. That is, it isn't sent as a separate message like the other administrative messages, instead it looks like this: > subscribe xyz-l Joe User Sorry, the XYZ-L list is closed. Contact the list owner for more information. You can't configure command replies, only the letters. But you can indeed set the list to By owner, and configure the letter sent to new subscribers. You can set it so that it only goes to the user and not to the owner. I do that for FISH-ECOLOGY. Eric