The following message to zcekiz@hotmail.com was undeliverable. The reason for the problem: 5.3.0 - Other mail system problem 550-"5.7.515 Access denied, sending domain LISTS.FSMPI.RWTH-AACHEN.DE doesn't meet the required authentication level. The sender's domain in the 5322.From address doesn't meet the authentication requirements defined for the sender. To learn how to fix this see: https://go.microsoft.com/fwlink/p/?linkid=2319303 Spf= Pass , Dkim= Fail , DMARC= Pass [VI1P190MB0783.EURP190.PROD.OUTLOOK.COM 2026-05-07T08:40:22.804Z 08DEABB71DB031DD] [MN0PR04CA0026.namprd04.prod.outlook.com 2026-05-07T08:40:22.858Z 08DEABE19A24AA79] [BL02EPF00029929.namprd02.prod.outlook.com 2026-05-07T08:40:22.864Z 08DEA73C6A865428]"