Reverse DNS Exchange 2003

[Bill Driscoll]

Within the past two weeks, just started receiving the following:

The following recipient(s) could not be reached:

somebody@domain.com on 1/11/2005 5:39 AM
You do not have permission to send to this recipient. For
assistance, contact your system administrator.
<sbs.servername.local #5.7.1 smtp;554 5.7.1 The server sending
your mail [66.234.132.###] does not have a reverse DNS entry. Connection
Rejected. Please contact your Dial-Up/DSL/Network ISP Provider. Default
Reject!>

When my client (using SBS2003) reported the problem, I sent a message to the
recipient from our server (SBS2000) and received the same reply.

We are both using Network Solutions for DNS hosting and they have verified
the reverse DNS. Is there some other configuration I need to do on the
Exchange Server 2003? The client server has been up since last January and
ours has been up for over four years.

[Lanwench [MVP - Exchange]]

Bill Driscoll wrote:

Within the past two weeks, just started receiving the following:

The following recipient(s) could not be reached:

somebody@domain.com on 1/11/2005 5:39 AM
You do not have permission to send to this recipient. For
assistance, contact your system administrator.
sbs.servername.local #5.7.1 smtp;554 5.7.1 The server
sending your mail [66.234.132.###] does not have a reverse DNS entry.
Connection Rejected. Please contact your Dial-Up/DSL/Network ISP
Provider. Default Reject!

When my client (using SBS2003) reported the problem, I sent a message
to the recipient from our server (SBS2000) and received the same
reply.

We are both using Network Solutions for DNS hosting and they have
verified the reverse DNS. Is there some other configuration I need
to do on the Exchange Server 2003? The client server has been up
since last January and ours has been up for over four years.

Network Solutions doesn't have anything to do with it. It's your ISP itself
that can create/control the reverse-lookup - they own the IP/netblock. You
haven't posted the unedited IP address, so I can't check, but you can - in a
command prompt, type

ping -a <ipaddress>

and see what you find.

Note that you may run into this problem with some very picky mail servers
even if your public IP *does* have a reverse lookup record, for several
reasons - if it doesn't exactly match the FQDN of your mail server (eg.
server01.mydomain.com), if you're on a dynamic IP range, etc etc etc -

It may be easiest just to set up SMTP connectors that forward all outbound
Internet mail to the ISP's SMTP server as a smarthost. Or just mail destined
for this domain/ISP (although you may have to continually add domains that
are hosted by said ISP to the list, which can be a pain).