Before you send out an email campaign, you must set the email opt-in required for email delivery.
Follow these steps to set the required email opt-in:
- Log in to your CRM account.
 	- Click the Main Menu.
 	- Click Settings.
 	- Select Email Settings under Configuration.
 	- Scroll down to the Required Opt-in for Email Delivery setting.
 	- Choose the opt-ins from the Email Opt-ins drop-down.
 	- Click Save.
 
Note: You can access Settings only if you are an Admin user. 
Which opt-in types allow you to send email campaigns Vtiger does not deliver emails to contacts with opt-in set to ‘None’, ‘Opted out (user)’, or ‘Opted out (contact)’.
Email campaigns are delivered only to contacts with opt-in set to:
- Single opt-in (user)
 	- Single opt-in (webform)
 	- Double opt-in
 
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