• The complete email header can be used to track down the sender of an email address. The email header contains routing information and email metadata, both of which you should ignore. However, that information is critical in determining the email's origin.
• Open your Gmail account, then open the email you wish to track down. Show original from the menu by selecting the drop-down menu in the top-right corner.
• Full Outlook Email Header: After you've double-clicked the email you wish to track, go to File > Properties. The data is found in the internet headers.
• Full Email Header in Apple Mail: Open the email you want to trace and go to View > Message > Raw Source.

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