To all who responded (and there were many) - and helped me solve the problem: Many thanks - that seems to have been the problem: bounced mail from that one address (altho why it wound up with that kind of error message, I don't know). But - I have solved the problem, and set the subscriber to 'nomail'. Thanks to all of you.... David Silberberg Blues-l Co-list-mom [log in to unmask]