Sorry I've been such a bother with this, but I really appreciate the information and advice (and thanks also to Melvin Klassen). I guess the reason these people are getting so many error messages must be because a lot of subscribers have broken mailers. I subscribed to the list and you can't send anything without getting several error messages. It's frustrating not being able to do much about their problems, though I think I've taken care of a few. I would swear I've seen the Errors-To: line in some email headers, but I accept your word it isn't standard. Thanks again, no more questions (for now) :-) Douglas Winship Austin, Texas [log in to unmask] Secondary AUTOCAT Listowner