Exchange 2K open relay problems and @[192.1.1.1] 2

[JoeTech64]

We're running Ecxchange 2K with SP4 and last week we were
hit with thousands of unwanted spam, due to an open relay
problem on our server. Since then, we've changed our server's SMTP virtual server's setting: \Access\Relay, and
selected "only the list below" with the list blank and I
unchecked the "Allow all computers which successfully
authenticate to relay." I even tried re-checking this
option and still no success.

Our open relay seems to be resolved (Telnet test from the
outside did not open our ip) and our over flooded queue's
cleared. We reomved ourselves from black list sites, all
accept for one.

http://www.dsbl.org

wants to send us an email to postmaster@ourdomain.com or abuse@ourdomain.com, but is unable to due to an error, "confirmation email refused. Please fix your server to accept removal request mail."
Such email accounts do exist but still can't receive mail.
I can't figure out how to do this and hence, can't remove
our server from said black list.

Everything indicates all is well but we can not send or
receive any mail. Plus, any mail sent from the outside in,
does not get delivered or returned to original sender.

I've tried re-starting all the services with no success.
Does anyone have any suggestions on to what the problem(s)
could be?

Thanks in advance.

 

[mdcr]

Question - then NDR's are bad to have enabled? Do spammers receive the NDRs and take action based on them? I would think that if a spammer sent out 1000 emails and got 999 NDRs back, he would only continue to send email out to that one person who was valid, right? Any resources you can recommend as to more information on this subject? Thanks....

 

[crobin1]

My opinion is that NDRs have become less than useful, through no fault of their own. Due to so many spam/viruses, it's basically a waste of resources.
[ul]
[li]A lot of NDRs to spammers won't even make it, because the spammers forged the To or Reply-To address. This waste resources on the mail server trying to send the NDR.[/li]
[li]Since so many viruses are forging the From address, NDRs back to those addresses are useless since that person didn't send the message in the first place. This waste the server's time sending the NDR and the receiver's time having to read it and delete it.[/li][/ul]

 

[JBruyet]

mdcr, and anyone else wondering about NDRs. As I understand the situation the purpose of having a spam filter send an NDR to a spammer is supposedly to let him or her know that the e-mail address they sent the spam to is not a valid address. The thought was the spammer would say, "Oh, that's not a good e-mail address. I won't send any more spam to that e-mail address." Yeah, right.

crobin makes a good point about forged addresses--the NDR won't get back to where the spam came from so it won't do any good. AND, a mail server could possibly get a ton of bounced NDRs coming back. What a mess.

Just my thoughts FWIW,

Joe Brouillette