Subject: Undelivered Mail Returned to Sender
From: Mail Delivery System <[email-masked]>
To: [email-masked]
Date: Wed, 07 Jan 2026 10:00:05 -0800

This is the mail system at host mail.meridiansupply.example.

I'm sorry to have to inform you that your message could not be delivered
to one or more recipients. The error is shown below.

  <[email-masked]>: host mx.nonexistent.example said:
  550 5.1.1 The email account that you tried to reach does not exist.