--- The message cannot be delivered to the following address. ---
email@example.com Mailbox unknown or not accepting mail.
550 5.1.1 <firstname.lastname@example.org>... User unknown
Diagnostic-Code: X-Notes; Cannot route mail to user (email@example.com).
--- Begin Message ---
Follow the instructions to read the message.
File attachment: data.zip
The file attached to this email was removed
because the file name is not allowed.
--- End Message ---