Use the available deliverability options to configure your Salesforce org so that your users’ emails from Salesforce get where they’re going fast.
|Available in: Salesforce Classic and Lightning Experience|
|Available in: All Editions except Database.com|
|To configure email deliverability:||“Customize Application”|
From Setup, enter Deliverability in the Quick Find box, then select Deliverability.
Select the options that apply to your Salesforce org.