Jenkins : poll-mailbox-trigger-plugin and SMTP - jenkins

Question

I am unable to get Jenkins to build based on an email using the poll-mailbox-trigger plugin
My setup in E-mail Notification is as follows
SMTP server: myExchangeServerHostName
Default user e-mail suffix: #companyName.com
Use SMTP Authentication: True
User Name: DOMAIN\user
Password: aboveUserPassword
Use SSL: False
SMTP Port: 587
Reply-To Address:
Charset: UTF-8
From here I can successfully send a test email to myself and I receive it.
In my build the Poll Mailbox Trigger settings are as follows
Host: myExchangeServerHostName
Username: DOMAIN\user
Password: aboveUserPassword
Advanced Email Properties:
mail.imaps.port=587
mail.imap.ssl.enable=true
mail.imap.starttls.enable=true
Schedule: H/5 * * * *
When Testing this connection I get
Connecting to the mailbox...
Error : javax.mail.MessagingException: Unrecognized SSL message, plaintext connection?;
nested exception is:
javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection?
at com.sun.mail.imap.IMAPStore.protocolConnect(IMAPStore.java:665)
I have tried
mail.imap.ssl.enable=false
using the email address instead of the domain\user
adding mail.imaps.ssl.trust=*
None of the above seem to make any difference.

Answer 1

SMTP protocol is for sending and relaying mails. With this protocol one cannot retrieve mails from a particular mailbox. Whereas IMAP and POP3 protocols can retrieve mails.Therefore you will have to obtain access to the IMAP or POP3 server in order to retrieve mails. The poll mailbox trigger plugin of jenkins tries to connect to mailbox via IMAP store. If the mail server is using HTTPS protocol like in an Exchange server, you can write a powershell utility using Microsoft EWS managed api, to retrieve mails and plug that utility into jenkins. Also, Powershell scripts can be included in batch scripts as well which can then be included in jenkins.

Answer 2

The problem might relate to the certificate on the mail server (self signed one, and not recognized by Jenkins and the plugin), so registering the certificate to your trustStore would help.
I found 2 working solutions:
Add the certificate of your mail server, following 'Highway of Life' instruction in Jenkins "unable to find valid certification path to requested target" error while importing Git repository
Change trustStoreType to Windows-Root so Jenkins would use the same certificate source as your browser, answer from 'Nux' here, How to configure trustStore for javax.net.ssl.trustStore on windows?
Note: solution 1), there were same answer but exporting the certificate from browser instead of using 'openssl', somehow it did not work for me or I did it wrong. So you may try both.