Outlook: Attach an Email to an Email
View your Microsoft 365 Email - Attach an Email to an Email instructions in this brief video or take a look at the step by step instructions below.
In the list view, select the message you want to attach and press Ctrl+C to copy it.
Create a new message. In the body of the new email, press Ctrl+V to attach the copied email. The copied email will appear as an attachment in the new email.