I am getting the following NDR when

[kavita11]

I am getting the following NDR when I try to send email to some domains. rr.com in particular.


The recipient was unavailable to take delivery of the message
The MTS-ID of the original message is: c=US;a= ;p=MYDOMAIN;l=MYSERVERNAME -030424210339Z-312
MSEXCH:IMS:MYDOMAIN:Houston:MYSERVERNAME 3499 (000B09AA) Host unreachable.

I have 2 exchange 5.5 SP4 servers. One of them is outside the firewall and one inside the firewall. I have generic SMTP handler enabled on the RAPTOR firewall but the exchange server outside the firewall is also unable to send emails to rr.ccom so the firewall really does not matter.
I have checked my DNS settings on both Primary as well as secondary, I even have reverse lookup enabled. We are not blacklisted either but still the mail does not go out.

HELP, I am out of options....

Thanks
Kavita

 

[dmc241]

Unless you've already fixed this...

I'd firstly check that DNS is translating the address for you. Start NSLOOKUP and enter "set type=mx" then "rr.com" (you might want a bigger than normal dos window for these guys).

This should tell you that the preference 10 server is, in this case, vamx02.mgw.rr.com. From your SMTP server, see if you can ping the name and/or the IP address.

If that works, see if you get a welcome msg when you "telnet vamx02.mgw.rr.com 25". Type "quit" to exit (you may not see the text).

If all this works, I'd contact their techos and see if they've had any "transient" problems.

Good luck.