incorrect spam setups cause spool messes on forwarders

Randy Bush randy at
Mon Dec 1 18:10:43 UTC 2003

is the following a general problem, or just one i am seeing?

note 2821 says

      450 Requested mail action not taken: mailbox unavailable
         (e.g., mailbox busy)
      550 Requested action not taken: mailbox unavailable
         (e.g., mailbox not found, no access, or command rejected
         for policy reasons)


From: Randy Bush <randy at>
To: foo at
Subject: broken mail server
Date: Mon, 1 Dec 2003 10:02:34 -0800

you have a .forward on pointing to foo.user at
like all mail accounts these days, you get spam.  but the forward,
as opposed to rejecting it with a 5xx is deferring with a 450 (see
below), which is not proper.  this means that the spam stays in the
queue here, which is just not reasonable.

please do one of the following:
  o see that the verison server is fixed (good luck),
  o set your forward to a properly working server, or
  o tell me so i can kill your mail account here.


2003-12-01 10:09:05 1APbBa-000Ork-DY == foo.user at <foo at> R=lookuphost T=remote_smtp defer (0): SMTP error from remote mailer after MAIL FROM:<nikkiadamczyk at> SIZE=5365: host []: 450 Requested mail action not taken-Try

More information about the NANOG mailing list