> If sandals.richw.org should not require SASL authentication, then > you should not turn on SASL authentication on sandals.richw.org.
Ah. Indeed, I had inadvertently enabled SASL authentication in the Sandals SMTP server (smtpd_sasl_auth_enable = yes in that server's Postfix configuration). This is turned off now. Thanks. Am I correct, though, in understanding that if I use sender-dependent authentication (smtp_sender_dependent_authentication = yes), then any given sender address (with a username / password specified in Postfix's SASL password map) is always going to use the same sender-dependent username / password info for *all* relay hosts that need authentication? In other words, if I need a given sender address to use one username / password when sending something to relay host A -- and a different username / password when that same sender is sending something to relay host B -- am I currently out of luck? Rich Wales ri...@richw.org