Mail sending failed_ Unrecognized SSL message, plaintext connection?

Log error trace:

Caused by: javax.mail.MessagingException: Could not connect to SMTP host: smtp.office365.com, port: 587;

nested exception is:

javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection?

Solution:

Error trace means that your exchange is expecting the connection in Plain Text but we are trying to connect using SSL/TLS.

Please check with your exchange admin if Plain Text Connection is enabled on the mail server? If yes, then please set the protocol in Outgoing Settings to 'SMTP' with TLS set to 'No' and port 25 and save the settings.

Once this is done, please check if mail sending is working.

If the issue persists, immediately zip the logs folder.

Please raise a ticket with us by sending an email to support@servicedeskplusmsp.com. Once you receive a ticket ID, upload the logs in https://bonitas2.zohocorp.com/ along with the ticket ID.

Note: While uploading, choose the product as Servicedesk Plus MSP, provide your email address and mention the ticket# in the comments box. Also Mention the issue recreated time for sure which will help in quicker analysis.