set DNS in email

Hi,

I want to track the emails which are sent from my portal site.

I want delivery notification for each email sent.

I have heard about the Delivery Status Notification(DNS) which needs to be set while sending email, but I couldn't find any solution of integrating using codeigniter mail function.
How should I use it.

If any other method that can track send emails, please provide me the step by step process.

Thanks.

1. Wrong board
2. Why do you need it?
3. If you use dns: The user get a Pop up.
4. Pixel and link click