incorrect spam setups cause spool messes on forwarders

Jared Mauch jared at
Mon Dec 1 18:31:41 UTC 2003

	I think you will find that people who want to reject the spam
but don't want to accidentally reject real mail will sometimes
use 45x instead of 55x error codes.

	I know when i was rejecting spam at the SMTP layer
I first started rejecting with 45x and watched my logs
for those pesky false positives.

	there might be some thought about punish the disk space of
those that are trying to deliver the spam to you ...

	- Jared

On Mon, Dec 01, 2003 at 10:10:43AM -0800, Randy Bush wrote:
> 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)
> randy
> 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.
> randy
> 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

Jared Mauch  | pgp key available via finger from jared at
clue++;      |  My statements are only mine.

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