We recently discovered an issue with Outlook classifying legitimate Emails as junk. Valid emails from clients as well as emails from within our organization were being sent to our junk folder.
Here is the header of such an email.
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Received: from AM6PR05MB4214.eurprd05.prod.outlook.com (2603:10a6:20b:92::30) by AM7PR05MB6775.eurprd05.prod.outlook.com with HTTPS via AM6PR04CA0017.EURPRD04.PROD.OUTLOOK.COM; Tue, 10 Mar 2020 10:06:37 +0000 Received: from AM0PR01CA0037.eurprd01.prod.exchangelabs.com (2603:10a6:208:e6::14) by AM6PR05MB4214.eurprd05.prod.outlook.com (2603:10a6:209:42::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.2793.17; Tue, 10 Mar 2020 10:06:35 +0000 Received: from HE1EUR01FT034.eop-EUR01.prod.protection.outlook.com (2603:10a6:208:e6:cafe::a6) by...