I'm running Exchange 2003 server. Recently one of the users reported a following error;

 'joshua@furman.com' on 7/11/2006 3:50 PM
            There was a SMTP communication problem with the recipient's email server.  Please contact your system administrator.
            <bbbnts.bbbntd.local #5.5.0 smtp;554 EMail from mailserver at is refused. See http://spamblock.outblaze.com/>

I went to sorbs website and found out that our server is black listed with following reason;
Dynamic/Generic IP/rDNS address, use your ISPs mail server or get rDNS set to indicate static assignment.

We are behind a NAT firewall, adn bbbnts.bbbntd.local is hour internal host name of the server. Actual domain name is b3law.com

How do we resolve this issue?
Who is Participating?
SembeeConnect With a Mentor Commented:
That is Postini. They have a smart host that you can send your email through. You will need to contact them to find out what it is for your account.

See this link for how to setup an SMTP connector to deliver through a smarthost:
You will also be tripped up because your server's SMTP banner is bbbnts.bbbntd.local - you should change that as well, so that it matches what the server is known as on the internet.


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mavrukinAuthor Commented:
OK. great. Is there a way to resolve this issue without using ISPs smart host? I read the links you sent me. One more problem I'm having with creating rDNS is that we use a 3rd party spam filter company and our email comes in to a different address, not our server itself. Our 3rd party spam filtering service then forwards us the emails then. So our emails leave from one IP address (ip address for our firewall) , and they are being forwarded to another IP address.  
this is our current MX records.
b3law.com       MX preference = 30, mail exchanger = B3LAW.COM.S5B1.PSMTP.com
b3law.com       MX preference = 40, mail exchanger = B3LAW.COM.S5B2.PSMTP.com
b3law.com       MX preference = 10, mail exchanger = B3LAW.COM.S5A1.PSMTP.com
b3law.com       MX preference = 20, mail exchanger = B3LAW.COM.S5A2.PSMTP.com

What to do in this situation?

You will probably have to send your email through the third party's servers. That is the best idea. Then it comes out of the servers that are responsible for your domain.

mavrukinAuthor Commented:
do you mean my ISP or my spam filters? Spam filtering servers only scan for incoming, they don't send out email.

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