What is the From Email SMTP Server in Mail Settings?
Whenever a email is sent from this App, connections are made with the SMTP server to handle the sending. For example, let's assume my from email is email@example.com, my SMTP can potentially be mail.mydomain.com or smtp.mydomain.com or another address as set by the server.
This information is available from your tech support team. If you use a popular email service such as Gmail or Yahoo! Mail, you can also find relevant information on SMTP Settings by searching key phrases such as "Gmail SMTP Server".
SMTP servers for popular mail services:
(Always double check official websites for most up to date information)
Apple / iCloud