Get the full headers of an email in Outlook

Open the email, and in the Ribbon, click on the anchor at the bottom right of the “Tags” section to open the Message Properties.

At the bottom of the Message Properties are the message headers. Right-click and Select All, then copy them.

Close the Message Properties and forward the email. Select the headers that appear in the email forward (From, Date, To, Subject) and paste in the full headers you copied in the previous step.