Self-Destructing-Email is the original tracking service of its kind, and remains the most powerful and reliable email and document tracking service in the world today. In short - Self-Destructing-Email tells you when your tracked emails and documents are opened / re-opened / forwarded and so much more.
Create an account at http://www.self-destructing-email.com/ , follow up the instructions & then go to your email and send a message with .self-destructing-email.com attached to the recipient's mail.... After that you will be notified at the self-destructing-email what happens with it :)
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