Subject: Returned mail: see transcript for details

From: Mail Delivery Subsystem <[email-masked]>
Date: Wed, 11 Jun 2025 12:36:15 +0200

The original message was received at Wed, 11 Jun 2025 12:36:14 +0200
from m0417413.ppops.net [127.0.0.1]

   ----- The following addresses had permanent fatal errors -----
<[email-masked]>
    (reason: 550 5.4.1 Recipient address rejected: Access denied. For more information see https://aka.ms/EXOSmtpErrors [AM3PEPF0000A79B.eurprd04.prod.outlook.com 2025-06-11T10:36:15.310Z 08DDA8550852B4F4])

   ----- Transcript of session follows -----
... while talking to brenntagnordic-com02b.mail.protection.outlook.com.:
>>> DATA
<<< 550 5.4.1 Recipient address rejected: Access denied. For more information see https://aka.ms/EXOSmtpErrors [AM3PEPF0000A79B.eurprd04.prod.outlook.com 2025-06-11T10:36:15.310Z 08DDA8550852B4F4]
550 5.1.1 <[email-masked]>... User unknown
<<< 503 5.5.2 Need rcpt command [AM3PEPF0000A79B.eurprd04.prod.outlook.com 2025-06-11T10:36:15.310Z 08DDA8550852B4F4]