Mail headers can be interesting to inspect possible delays of mails or to retrieve the origin of spam and phishing mail.
This is how you can find the mail headers in Apple Mail.
1. Select the mail of which you want to see the mail headers.
2. Go to the menu "
View" .
3. Select "
Message" .
4. Select "
Raw Source".
The Mail Headers will appear in the content of the e-mail.