How do I view e-mail headers in Mail for Mac OS X?

  1. Open Mail.

  2. From the Mail menu, select Preferences.

  3. Click the Viewing icon.

  4. Click the arrow box on the Show header detail pop-up list and choose All.

  5. Close the Viewing window. The e-mail headers should now be displayed in the message.

If you intend to send these headers to another person for review, then double-click the message.

  1. Click the Forward button.

  2. Finally, fill in the To field and send the message.