The problem I had was errors was that upon verification none of the error messages were reason to remove the person from your list. In most cases the follow-up proved that the mail had actually been received and the participants were content and not bouncing the mail. So you can't just remove the participant immediately. I have never bothered to find out where the errors are generated but it is being followed up. I have been running conferences for more than 2 years now and I have seen all of the problems come and go from various recipients. Someone on another list joked about the ease of generating the message "host unknown" as a false error message. I would check before I just removed the participant from the list at any rate as these messages seem to be singularly un reliable. Best regards, Paul. -- Dr. Paul S. di Virgilio, University of Toronto [log in to unmask]