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ESD is Unable to Establish a Connection to the OCI Email Delivery Service as the SMTP Server. It is Failing with '451 Connection or protocol error' (Doc ID 3004067.1)

Last updated on MARCH 27, 2024

Applies to:

Siebel Marketing - Version 17.0 [IP2017] and later
Information in this document applies to any platform.


The Email Sending Daemon (ESD) is configured to send email through the OCI Email Delivery Service, but is failing to establish a connection. When starting the ESD Service, it shutdowns automatically after a few seconds.

From the esd.log file, the following error is observed:

451 Connection or protocol error: com.siebel.sem.smtp.SMTPException: Unexpected response at authentication user: 235 Authentication successful.
2023-12-06 12:20:52,679 [SMTPTalker-37] DEBUG SMTPTalker Caught AbandonHost
com.siebel.sem.smtp.AbandonHostException: Error with current domain: Giving up on domain local MTAs: com.siebel.sem.smtp.SMTPException: Unexpected response at authentication user: 235 Authentication successful.. Giving up on domain for now
at com.siebel.sem.smtp.SMTPTalker.connectAndHelo(

Note that the log file is a little misleading as we see '235 Authentication successful', but is actually failing to establish a connection as we can see from the Java error.

The issue can be reproduced at will with the following steps:

1. Configure ESD to connect to the OCI Email Delivery Service following the documentation:
Marketing Installation and Administration Guide > Installing and Configuring Siebel Email Marketing > Process of Configuring the Email Sending Daemon

2. Start-up the ESD Daemon service


Due to this issue, ESD is unable to use the OCI Email Delivery Service to send emails.


Configuration to OCI Email Delivery Service


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