Relay Access Denied SBS 2003

Getting this back from some emails sent:

You do not have permission to send to this recipient.  For assistance, contact your system administrator.
            < #5.7.1 smtp;554 5.7.1 <>: Relay access denied>

We have SBS 2003.   We have a T1 service that has worked for us with no problem.  I have a PTR that point to our mail server and the MX records points to our domain. No problem there.

This problem started when I added a second line - FIOS verizon service.  I am trying to load balance the 2 lines.  I had Verizon setup a PTR  to point to our mail server, however when I do an mx look up, the mx record still points to the T1 static IP.

I assume I need to get the FIOS service to setup up an MX record as well to where it points to our mail serve?

Is it okay to set it up this way? basically 2 PTRs to the MX?  Not sure what the standard practice is here.
Who is Participating?
Simon Butler (Sembee)Connect With a Mentor ConsultantCommented:
The problem is, Exchange can only use a single banner for outbound traffic. As you cannot have the same host name on two differnet IP addresses PTR, you are going to get problems with any site that is being picky.

If you have SPF records, then ensure that both host names are listed. MX records aren't so important, as long as you have a valid host name that resolves to the correct place. However for outbound email you will need to either route all email via the same route, or use a smart host so that it doesn't matter how the email goes out to the external host.
If you are using a smart host now, ensure that it setup to accept email from your second connection.

Will SzymkowskiSenior Solution ArchitectCommented:
This is most likely a reverse DNS issue with with the second line. When Outbound mail is not configured properly and you are sending from 2 different external IP's your domain can get flagged by anti-spam appliances which is probably what happened.

MikejettAuthor Commented:
What would you recommend as a solution?  I do have a PTR with that second line that points to our mail server. I thought that would take care of it, however it didn't
MikejettAuthor Commented:

 Is there a way I can specify in Exchange which IP address to use for outgoing mail service?  

Simon Butler (Sembee)ConsultantCommented:
This is something that has to be done by your router.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.