How can I get confirmation that email was received

Question

Hi everyone. I heard that it is possible to get a confirmation immediately after someone had received and open an email from you. Does anybody knows how this is done?
Thank you very much for your inputs.

Answer 1

You can do this, although it's an undocumented feature of Mail. But if your recipient's email program is not setup to send a receipt, you will get nothing. In any case, if you want to do this:
1. Quit Mail
2. Open Terminal (in Applications/Utilities)
3. Enter the following text into the window, including all the quotes as is:
*defaults write com.apple.mail UserHeaders '{"Disposition-Notification-To"="you@address";}'*
replacing "you@address" with your actual email address, then press Enter. When finished, quit Terminal. All messages sent now will include a request for a Read Receipt.
If you ever need or want to turn off this feature, quit Mail, open Terminal and enter this line:
*defaults delete com.apple.mail UserHeaders*, then press Enter, then quit Terminal.
Mulder