Mac OSX email message report
You can enable a Read Request Receipt in Apple Mail, so if the receiver client support it, you'll get a "Read Receipt" back.

It is possible to add these headers to to outgoing mails:


"Disposition-Notification-To" (Read Request Receipt)
Bcc
"Reply-To"


To make Apple Mail request a read receipt for every message you send:


Open Terminal.
Type "defaults read com.apple.mail UserHeaders".
Press Enter.
If that command returns "The domain/default pair of (com.apple.mail, UserHeaders) does not exist":


Type


defaults write com.apple.mail UserHeaders '{"Disposition-Notification-To" = "Name &lt;email@address&gt;"; }'

replacing Name with your name and email@address with your email address.


The complete line could read defaults write com.apple.mail UserHeaders '{"Disposition-Notification-To" = "FirstName LastName &lt;sender@example.com>"; }'



And to add one of the other headers you just add it to the line - then the line could read like this:

defaults write com.apple.mail UserHeaders '{"Reply-To" = "ReplyFirstName ReplyLastName &lt;reply@example.com>"; Bcc = "BccFirstName BccLastName &lt;bcc@example.com>"; "Disposition-Notification-To" = "FirstName LastName &lt;sender@example.com>"; }'