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 [AS8P190MB1320.EURP190.PROD.OUTLOOK.COM 2026-05-12T16:25:00.219Z 08DEAF968263E212] [CH3P221CA0006.NAMP221.PROD.OUTLOOK.COM 2026-05-12T16:25:00.307Z 08DEB0099E59B573] [CH2PEPF0000009C.namprd02.prod.outlook.com 2026-05-12T16:25:00.298Z 08DEADE0B9F323EE]"