To configure newsletter settings on your site:

In your Magento admin go to System -> Configuration -> (Customers on the left) Newsletter

to open the configuration page. There you are going to see the following fields:

 

 

 Success Email Template: select a template to use for the email that your customers receive when they successfully subscribe to your newsletter. You can use the default or select a
different template.

– Unsubscription Email Sender:  select which store email account is used to send unsubscription emails.

– Unsubscription Email Template : select a template to use for the email that your customers receive when they unsubscribe from your newsletter. You can use the default or select a
different template.

– Success Email Sender: select which store email account is used to send emails informing your customers that they have successfully subscribed to your newsletter.

– Confirmation Email Template: if you require customers to confirm their newsletter subscription, select a template to use for the confirmation email. You can use the default or
select a different template.

– Need to Confirm: set whether customers must confirm that they want to subscribe to your newsletter. Select Yes to specify that each customer that registers for a newsletter will
receive an email asking them to confirm their registration. This technique is called double opt-in, meaning that customers confirm that they want to receive a newsletter twice. This method reduces the number of customers that consider your newsletter as spam.

– Confirmation Email Sender: if you require customers to confirm their newsletter subscription, select which store email account is used to send confirmation emails.

-Allow Guest Subscription: set whether you want to allow guest (unregistered) customers to subscribe to your newsletter.