Re: Sorbs.net DNS Blacklist

[John Mason Jr <john.mason.jr () cox net>]

Dan Denton wrote:
> I've got some updated info since the original posting. I spoke by email
> with a gent at payments () sorbs net, and was told that the reason we were
> blacklisted was that a spammer sent a message from a forged username at
> a particular domain. The email hit an address at our server that was no
> longer in use, and of course a bounce message was sent back saying the
> address doesn't exist. 

The "proper" way to deal with this is to reject during the smtp 
conversation, that way your mailserver will not generate the bounce 
message and get stuck in a blacklist.

<http://spamlinks.net/prevent-secure-backscatter.htm>

> Evidently, this response is considered spam in and of itself by
> sorbs.net, and that's what got us on the blacklist. Never mind that we
> were the ones who got spammed in the first place, and our mail gateway
> was only doing what it was supposed to do. I was told that if we ceased
> such "harassment", then we would be removed from the blacklist. 


Backscatter is bad, I hope you can find a way to fix your problem
The link explains it better than I can


> Symantec, who makes our gateway, has it documented on their website that
> this feature cannot be disabled, and that such responses are required by
> RFC 821. I can see the point. If there's no response to the sender of an
> email who accidentally puts a typo in the email address they're sending
> to, how the heck would they know if their email reached the correct
> party or not? They'd receive no response from a real user, and they'd
> probably wonder why they're being ignored. In a business setting, that
> behavior could lose you money real quick.

It is not about getting the NDR but which server should generate it.



John

<snip>


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