E-Mail Rejection Issue

[HaierIT]

Good afternoon, we have having a very strange issue. We have one of our customer trying to e-mail us but they keep getting the following kick-back message. This is the only customer that is having issues e-mailing us. Below is the message they receieve. Keep in mind that we have a SPAM SonicWall Mail Frontier server on our side but I have added their domain to our trusted list. Can anyone shed some light on the message below and what I can check. Thank you.


???@???????.com
SMTP error from remote mail server after initial connection:
host mail-in.???????.com [??.???.??.???]:
421 4.7.1 Delivery not authorized, connection refused, code=GL42:
retry timeout exceeded

 

[ShackDaddy]

What are you seeing in the SonicWall logs? Is there any server that the mail has to route through before it arrives at your SonicWall?

It looks to me like the connection is being dropped immediately based on RBL'd IP subnets or something.

Go to DNSStuff and run a report on the sending domain and see if they have an RDNS record in place or if there are any other issues with their sending environment.

Dave Shackelford
ThirdTier.net

 

[wahnula]

Dave,

DNSStuff is no longer free. Google "free DNS report" and you'll find a handful still exist like:

http://www.dnscolos.com/free-dns-report.html

...which though not as comprehensive as DNSStuff is still useful.

Tony

Users helping Users...

 

[HaierIT]

Hey ShackDaddy, the logs on the SonicWall did not show anything. No trace of the e-mail even reach and being rejected.

I did solve the issue, I got the IP Address of the senders mail server and then manually added their address to our Sonicwall. At first I included the senders mail server Host Name to our White List on the Sonicwall but that did not work. Once I added their IP address everything started working.

thanks guys. Case closed.

 

[ShackDaddy]

Cool. That pretty much confirms that it was a connection-based filter by IP address that was causing the drop. Those types of drops happen before everything else, and are often not even logged, since the SMTP session didn't even really kick off.

Dave Shackelford
ThirdTier.net