Business Manager Email Configurator

Use the optional email settings to define your own SMTP server for customer and platform email delivery.

When you configure this option, your customer email uses the SMTP server that you set up in the configurator. If you don’t set a custom configuration, your customer and platform email continue to use the default SMTP server that Salesforce provides.
Note: If you check use this custom email configuration but don’t complete the configuration setup, customer and platform email don’t work.
You can set the configuration to use the server for customer and platform email or customer email only. When you set the configurator for customer email only, the platform notification email uses the default SMTP server.
Note: The SMTP server must support STARTTLS.