Outlook return secured certificate that cannot be verified when trying to using SSL

Email > Troubleshooting email problems and errors
When setting up SSL using your outlook or similar software, you will receive an error saying "secured certificate that cannot be verified", or "certificate error".  This is normal because you never purchased a SSL certificate for 'mail.yourdomian.com'.  If you would like to fix this error, you'll need to do the following:

1) Go to Control Panel ---> Emails --->  Click on "Manage users&quotas" 
You will see the mail server address on the page:
Such as mail5016.site4now.net, we have SSL installed on our mail server address, so that you can use mail server address directly instead of use mail.yourdomain.com

Otherwise, you can simply ignore the error and uncheck SSL/TLS will continue to work.