The following message to nadyasergeyeva@outlook.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 [GV1P195MB2613.EURP195.PROD.OUTLOOK.COM 2026-06-12T12:49:22.548Z 08DEC79F5DA7A8FF] [DB9PR01CA0001.eurprd01.prod.exchangelabs.com 2026-06-12T12:49:22.547Z 08DEC7EA76D1BA38] [DU6PEPF00009524.eurprd02.prod.outlook.com 2026-06-12T12:49:22.563Z 08DEC79CDC0FB7FB]"