You don't have to issue a CHANGE command at all if they've already subscribed under their new address -- just delete the old one. There is one special case where this is confusing: when they've never subscribed under the new address and the old address is equivalenced via the LISTSERV alias facility. E.g., if I were subscribed as [log in to unmask] and want to change that to [log in to unmask], the CHANGE command would say that I'm already subscribed since we do in fact have that host address aliased. /Pete