It is important to inform your customers about new promotions and discounts. The Magento Newsletter functionality allows the store administrators to send newsletters to clients who are subscribed to them.
First you should enable the option for the customers to confirm that they agree to receive the newsletter. This feature can be turned on from the Magento Admin Area-> System-> Configuration-> Customers-> Newsletter. Expand the Subscription Options area and change the Need to Confirm field value to Yes.
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