Hi again, Sam. You're being very helpful, thanks again!
So given the information below, I have a followup question... Since a "<>" is a valid MAIL FROM, what are valid scenarios when mail servers would legitimately provide a "<>"? Besides a DSN notification, is there any other type of message which legitimately provides the empty sender? Is there some other header information which I could look at to "authenticate" the empty sender? In other words, if the junk mailers out there are sometimes using the "<>" empty sender, is there a way for me to tell whether this particular smtp session should or should not have an empty sender? Again, the objective here is to allow empty sender messages to pass through, but only if the empty sender seems "legitimate". Thanks Ricardo ==================================================== > Does courier accept smtp sessions where there's a RCPT TO but no valid > MAIL FROM? Courier requires a MAIL FROM. A "MAIL FROM: <>" specifies a valid, empty sender. > "authenticated" delivery system. However, I do need to let through > messages from postmaster/mailer-daemon and any other valid > system-generated messages, including DSN and the like. But if I also > allow any message with an empty sender, then it might defeat the purpose > of the system. Valid DSNs use an empty envelope sender, as defined above. There is a small minority of broken mail servers that use some randomly-generated, invented return address for delivery status notifications. They can be safely ignored, as hopelessly broken. > I thought that the $SENDER variable was set to whatever the "MAIL FROM" > was set to during the smtp session. Correct. If "MAIL FROM" specifies an empty return address, SENDER will reflect that. ------------------------------------------------------- This sf.net email is sponsored by:ThinkGeek Welcome to geek heaven. http://thinkgeek.com/sf _______________________________________________ courier-users mailing list [EMAIL PROTECTED] Unsubscribe: https://lists.sourceforge.net/lists/listinfo/courier-users
