Issue Summary

As an Administrator, I want to ensure that Jira is using a secure email channel whenever possible and with the combination of protocols and options, it's confusing and not intuitive for me to know how to setup my outgoing mail server in Jira.

Steps to Reproduce

1. Login to Jira as an Administrator
2. Click on Settings > System > Outgoing Mail
3. Click to Setup a new SMTP server in Jira
4. Try to determine if you need to use the SMTP, or SECURE_SMTP protocol, and if you need to use the TLS checkbox.

Expected Results

The UI is intuitive and allows me to simply connect to my SMTP mail system such as Office365

Actual Results

Finding the right combination of protocol and TLS check box is difficult and users could see various errors in the GUI

For example, we could see errors like this in the atlassian-jira-outgoing-mail.log

com.atlassian.mail.MailException: com.sun.mail.smtp.SMTPSendFailedException: 451 5.7.3 STARTTLS is required to send mail   

and also other errors like this:

DEBUG secure/admin/VerifySmtpServerConnection!update.jspa [c.atlassian.mail.outgoing] DEBUG SMTP: Attempt to authenticate using mechanisms: LOGIN PLAIN DIGEST-MD5 NTLM XOAUTH2
DEBUG /secure/admin/VerifySmtpServerConnection!update.jspa [c.atlassian.mail.outgoing] 
DEBUG SMTP: Using mechanism LOGIN
DEBUG /secure/admin/VerifySmtpServerConnection!update.jspa [c.atlassian.mail.outgoing] 
DEBUG SMTP: AUTH LOGIN command trace suppressed
DEBUG /secure/admin/VerifySmtpServerConnection!update.jspa [c.atlassian.mail.outgoing] DEBUG SMTP: AUTH LOGIN failed  

Workaround

The TLS checkbox should enforce StartTLS to help upgrade the connection to an encrypted method. Due to this, if you are struggling to setup an encrypted SMTP mail server then you will want to try:

• use the protocol SECURE_SMTP without the TLS checkbox
• or use the SMTP protocol with the TLS checkbox.