Related Questions:
Where do I find my email message id in Outlook?
Answer:
Browser Outlook
When viewing the relevant email, click the three dots on the right hand side
In the dropdown menu, click View
Click View message source
Copy everything you see in the window the opens
Paste the information to ET Support in an email or message
Desktop Outlook (Windows)
Double-click on the relevant email to open it outside of the Reading Pane
Click File > Properties
Header information appears in the Internet Headers box, copy all of that text
Paste the information to Support in an email or message
Desktop Outlook (Mac)
Right-click on the relevant email in your email list
Click View Source
Copy everything you see in the window that opens
Paste the information to Support in an email or message