Subject: Undelivered Mail Returned to Sender

From: [email-masked] (Mail Delivery System)
Date: Tue, 7 Oct 2025 15:52:52 +0200 (CEST)

This is the mail system at host mgw4.netic.se.

I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

                   The mail system

<[email-masked]>: host localhost[127.0.0.1] said: 550 5.7.1 This
    message is blocked due to security reason (in reply to end of DATA command)