On behalf of my alumni association, I use a service, WHATHELPS.COM which hosts three lists for us for a nominal monthly amount using listserv 1.8e. (A wonderful deal if you don't have the software and don't want to bother with all the maintenance and you don't have university accounts with major hardware and bandwith .... ) We average about 10 msgs a day on our list and are getting the following error about once a day and cannot figure out why. the email address is valid. Any ideas? Stan ----------------------------------------------------------------- The following 1 subscriber is currently being monitored: Err First Last Address --- ----- ----- ------- 1 07/19 07/19 John Gayer <[log in to unmask]> Last error: 5.1.1 Mailer [64.49.220.152] said: "550 5.7.1 Unable to relay for [log in to unmask]" Err= Number of delivery errors received thus far First= Date first delivery error was received (mm/dd) Last= Date of most current delivery error (mm/dd) Note: manually deleted subscribers may remain on the monitoring report under an alias address. Such entries will expire eventually; you do not need to do anything about them.