Hi @Megan ,
Welcome to our forum!
When I send messages to someone outside of Outlook, there is a black divider line + ****From: *** Sent: *** To: *** Subject: ******* block that is sent along with the body of my email, below my email signature.
What do you mean about "someone outside of Outlook"?
And does this issue occur in Outlook desktop client?
If so, please log in to your web mail and do the same test to check if there're any differences.
On the other hand, please check whether the message at the end appears as soon as you edit the email or after the email has been sent.
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