Emails are not being sent in Sandbox

Issue:

The workflow rules, approval processes emails etc. are not being received.

Solution:

Please make sure that "All email" is selected under the Sandbox's Deliverability.

Verify that 'All Email' is turned on in Sandbox Delivery Setting:

Classic: Setup> Email>Administration>Deliverability

Lightning: Click the gear icon > Setup > Email > Deliverability > Set the 'Access to Send Email' to All email

Save

Additional Information -

By default, email deliverability is set to 'System email only' in newly refreshed sandboxes.

If Access level is already 'All email' please troubleshoot the Workflow Rule Criteria - Set the Criteria for Your Workflow Rule.

If all the above seems to be fine, visit Testing Deliverability for additional troubleshooting steps.

Resource(s): https://help.salesforce.com/

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