SMTP relay configuration check

Question

SMTP relay configuration check

EDD118 0

Hi team

Our identity governance system isn’t sending notification emails for the quarterly access review. The process runs but no messages are delivered. I suspect an issue with the SMTP relay configuration on the mail gateway. Please, guide me on how to inspect or test the SMTP relay settings to confirm whether the connection and authentication are working correctly ?

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Answer 1

Hello EDD118,

When notification emails fail to send, the first step is to confirm whether the identity governance system can reach the mail gateway and authenticate correctly. A common way to test this is by using telnet <mailserver> 25 or openssl s_client -connect <mailserver>:25 to verify that the relay accepts connections. You should see a 220 banner from the SMTP service if the connection is successful.

Next, check whether the relay requires authentication. You can use tools like Send-MailMessage in PowerShell or smtp-cli to send a test message through the relay with the same credentials your application uses. If authentication fails, the relay logs (often in Exchange or your mail gateway) will show rejected attempts.

It’s also important to confirm that the relay allows messages from the application’s IP address. Many gateways restrict relaying to specific source IPs, so if the governance system was moved or reconfigured, the relay may now be blocking it. Reviewing the gateway’s allow list will help.

Finally, check DNS resolution and firewall rules to ensure the application can reach the relay host. Running a packet capture during a test can confirm whether traffic is leaving the server and being accepted.

I hope the response provided some helpful insight. If you find this answer useful, please hit “accept answer” so I know it addressed your concern.

Jason