Messaging Gateway

Seem to be having a problem with one client, inbound emails are received successfully, however when sending an email to this one client, users receive an NDR and the audit log shows the following error;

553 5.3.0 _dialup_reject_

After further investigation the problem is with one of the outbound scanner.

Setup:

x1 Control Centre

X2 Scanners

Hi,

You are talking about one client, by this you mean one recipient domain not on your site?

Or by other words, mails from one scanner to one internet domain fail with error "553 5.3.0 _dialup_reject_", right?

I personally havent seen these errors, no clue ;-)

But, what about telnet from one the working scanner and the other one?

Is there any difference in lan connection, ports, etc?

Are you using enforced TLS or opp TLS - possibly handshake errors, or non rfc compliant disconnect by offering client certificate, or cert errors anyhow?

I would suggest try telnet, then openssl, then tcpdump and you should figure out whats wrong.

Regards

Thomas

Apologies for the late response, got held up with something else.

With further investigation i have found the issue is with one of the scanners (scanner 2),  the email is delivered successfully through scanner 1. Both scanners are used for outbound/inbound and Exchange connector is configured for both in round robin.

I have replicated the configuration with the same scenario.

Setup:

x1 Control Center

x2 Scanners

x3 Exchange 2010