Jenkins email notification is successfully sent but not received

Question

When I run test emails from the Jenkins configuration page they are reported as "successfully sent" but only sporadically arrive (sometimes after a long delay) to internal company email. When I change the test email to send to an external (gmail) account it is immediately received.

I am using the company smtp mail server. I am able to telnet to it from Jenkins master and successfully send internal emails that way.

Jobs notification emails never arrive even though Jenkins reports it as:

Email was triggered for: Success
Sending email for trigger: Success
Sending email to: <MY EMAIL>

I couldn't find anything in the jenkins.log (but maybe I need to look at a different log?). Any help with troubleshooting the root cause would be great.

Answer 1

Answering my own question: I overlooked the SMTP settings in manage Jenkins page for the Extended E-Mail Notification plugin. It was only set for E-Mail Notification

Answer 2

Look at your SMTP server log to see if it queued the request and ensure it isn't stuck in a queue or dead message. It will also log if a SPAM or policy issue is causing the inconsistency.

Answer 3

I had a similar problem. I enabled 'Debug Mode' in Extended Email Notification under 'Manage Jenkins'. After enabling, I executed a job and in the build log, the Email notification verbose was printing. It seems my problem was with invalid credentials while typing password in SMTP Authentication. I hope this helps.