Subject: Returned mail: see transcript for details

From: Mail Delivery Subsystem <[email-masked]>
Date: Sun, 9 Nov 2025 16:39:05 +0100

The original message was received at Sun, 9 Nov 2025 16:39:04 +0100
from m0417415.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 [AM2PEPF0001C715.eurprd05.prod.outlook.com 2025-11-09T15:39:05.293Z 08DE1E89B24C306D])

   ----- 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 [AM2PEPF0001C715.eurprd05.prod.outlook.com 2025-11-09T15:39:05.293Z 08DE1E89B24C306D]
550 5.1.1 <[email-masked]>... User unknown
<<< 503 5.5.2 Need rcpt command [AM2PEPF0001C715.eurprd05.prod.outlook.com 2025-11-09T15:39:05.293Z 08DE1E89B24C306D]