2019
Finally – SMTP Authentication included with SharePoint 2019
https://blogs.technet.microsoft.com/mikelee/2018/07/25/finally-smtp-authentication-included-with-sharepoint-2019/
2013
Configure incoming e-mail settings - Error File Not Found?
https://social.technet.microsoft.com/Forums/office/en-US/5f6d864d-c2f7-4a1c-a86b-36bbf2890175/configure-incoming-email-settings-error-file-not-found?forum=sharepointadminprevious
Office 365
Configuring outgoing email settings for SharePoint with Exchange Online aka office365
http://blogs.technet.com/b/yashgoel-msft/archive/2014/03/06/configuring-outgoing-email-settings-for-sharepoint-with-exchange-online-aka-office365.aspx
How to Allow a Multi-function Device or Application to Send E-mail through Office 365 Using SMTP
https://technet.microsoft.com/en-us/library/dn554323(v=exchg.150).aspx
How to configure Internet Information Server (IIS) for relay with Office 365
https://technet.microsoft.com/en-us/library/dn592151(v=exchg.150).aspx
http://www.sharepointanalysthq.com/2014/07/sending-email-from-sharepoint-on-premises-via-office-365/