How to turn off Email Notifications in Salesforce?

The Email Notification can be turned off or the level can be changed using the below steps

1.       From Setup, click Email Administration --> Deliverability.
2.       Set the Access Level.

No access: Prevents all outbound email to and from users.
System email only: Allows only automatically generated emails, such as new user and password reset emails.
All email: Allows all types of outbound email. Default for new, non-sandbox organizations.

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