What is an email header?

An email header is hidden code within every email which contains important information about the sender, recipients and the how the email was routed across the Internet.

Our support team may ask you to provide us with email headers when troubleshooting email delivery issues, or whilst helping you setup DomainsFoundry Spam Protection – our powerful spam filtering solution included with our email and web hosting plans.

Below are steps for viewing and copying email headers information in the major email apps. If you don’t see your email app please reach out directly to your email app developer.

Microsoft Outlook (Windows)

  1. Open Microsoft Outlook.
  2. Double-click the email to open it.
  3. Click File > Properties.
  4. In the Properties window, look for the “Internet headers” section. This contains the email headers. To copy, highlight the header text and press Ctrl+C.

See View internet message headers in Outlook

Apple Mail

  1. Open Mail app on your Mac.
  2. Select the email.
  3. From the main menu choose View > Message > All Headers.

The email headers will be displayed. To cop, select all header text. Right click and choose Copy.

See Show detailed headers in Mail on Mac


  1. Open Thunderbird
  2. Select the email.
  3. From the main menu choose View > Headers > All.

See Getting started with the Thunderbird main window > Headers Pane

The email headers will be displayed above the message body. To copy, right click and choose Copy.