A feature that's new to SharePoint Server 2019 is SMTP authentication. In previous versions of SharePoint Server, servers in the farm could only send messages through an existing anonymous SMTP relay. With SMTP authentication, servers can log into a solution and send emails directly (such as through Exchange Online Protection or other systems).
SMTP authentication requires two configuration tasks to be carried out:
- Configuring an application credential key on each server in the farm
- Configuring outgoing emails for the farm
To configure SMTP authentication, follow these steps on each server in the farm:
- Choose an application credential key to use for the farm. This key will be used to encrypt and decrypt the stored password. This key must be the same on all servers.
- Launch SharePoint Management Shell.
- Run the following PowerShell commands, replacing the <ApplicationCredentialKeyValue> value with the application credential...