All Email Deliverability
Use the available deliverability options to configure your Salesforce org so that your users’ emails from Salesforce get where they’re going fast.
Enter the Setup screen by selecting the Gear in the top right corner.
Search Deliverability in the Quick Find box, then select Deliverability.
Select the option under access to All Email. This enables emails regarding status changes, requests, etc. to be sent from Orca to users.
Save any changes.
Find additional information about email settings, specifically deliverability Here.