I have a category set up to create topics using the simple mail receiver docker. This works fine if the custom email is in the ‘to’ field, but I can imagine users wanting to add the address as a CC when replying to a query (and so create a new topic). However at present this creates a hard bounce — the raw mail is below if this helps diagnose.
Original Message Headers
ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none;
b=RMdzOATFmy5T332lLPqvXDhUIG4noW+3JrFlhdHVgi4vgFkEgekprSnuttXd9nXVNC0e1zokeBWg6gX7HufnIawNoG8fTg0Mdi2CibU9qvWHuzNv62yMrQtGKdSQgAoMu8G+boXgoedt3bXaeYcWQnNNFazRo0Zv/9ZhwkIgf6nL8i+QqgCEV6rHln8TouZUaOnpiFfpf1eQsnCS2jmja24e5AoGsr/BckNS4A2GnC43mItHB4UcS+nTOe+9DQUYlDyYGXSW0z71NdQ0Wr6rp9Jxqi36N0ttEOicnquUJjVQLSUyLxSA+Jaeyx0mUO8A5T5qzPbae7hWHtRT03L0bw==
ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com;
s=arcselector9901;
h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck;
bh=VcKdFTK0IkrHVbOeqCF3xRkl6lH5ADRsiNsPwcYF3MM=;
b=AimZ+oZMcD1yQeWLzCIrVYzkCE+KAd2ALmCoEa7QACVTitoTwH4dp7//YFI/ZZfbgsYOQyFg9VzSR+77gxqpKS+xZJGxz1qy3wWi1iPtPslwTTsP+dBj0//IV0aI6Z1xPcGR9p5pt3D8wuMJZB/JAbF7vmYxYP27+dziPg5Q4WR/0mcZqAChR1jL9LYFhrHOnO+F4Pz6zXvtly050+MdyRJQXFgVuGgsLsoPbLPeOH3d07KfyNqm535NAFebuTB5nKxhwDBVKCD/dlBrD7Typ9ZcIiLe6zGlmUpcSO6V5zVQd4GI024xglRiB/ZHBQ+hsDkJ8FbVBBoIm8deqabHEQ==
ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass
smtp.mailfrom=sendingdomain.com; dmarc=pass action=none
header.from=sendingdomain.com; dkim=pass header.d=sendingdomain.com; arc=none
Received: from VI1PR03MB3680.eurprd03.prod.outlook.com (2603:10a6:803:36::18)
by VI1PR03MB6382.eurprd03.prod.outlook.com (2603:10a6:800:194::18) with
Microsoft SMTP Server (version=TLS1_2,
cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3933.31; Wed, 17 Mar
2021 17:26:09 +0000
Received: from VI1PR03MB3680.eurprd03.prod.outlook.com
([fe80::18bc:4b2b:7c8e:a29a]) by VI1PR03MB3680.eurprd03.prod.outlook.com
([fe80::18bc:4b2b:7c8e:a29a%3]) with mapi id 15.20.3955.018; Wed, 17 Mar 2021
17:26:09 +0000
From: Ben <ben@sendingdomain.com>
To: Ben <ben@gmail.com>
CC: "inboundaddress@discoursedomain.net" <inboundaddress@discoursedomain.net>
Subject: Test 3
Thread-Topic: Test 3
Thread-Index: AQHXG1KeYnOLfgK5wkiegVvRgKHEGQ==
Date: Wed, 17 Mar 2021 17:26:08 +0000
Message-ID: <0A90CCDB-EA9F-4F49-BE84-C5DF00991E2C@sendingdomain.com>
Accept-Language: en-GB, es-MX, fr-FR, en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
x-mailer: Apple Mail (2.3608.120.23.2.4)
authentication-results: gmail.com; dkim=none (message not signed)
header.d=none;gmail.com; dmarc=none action=none header.from=sendingdomain.com;
x-originating-ip: [2a02:c7f:5842:5b00:4d67:3770:8213:2dcc]
x-ms-publictraffictype: Email
x-ms-office365-filtering-correlation-id: c3f4160b-b9c6-444f-d45f-08d8e969c0f6
x-ms-traffictypediagnostic: VI1PR03MB6382:
x-microsoft-antispam-prvs: <VI1PR03MB63829F3EC03AE93C4723DA6DCD6A9@VI1PR03MB6382.eurprd03.prod.outlook.com>
x-ms-oob-tlc-oobclassifiers: OLM:1728;
x-ms-exchange-senderadcheck: 1
x-microsoft-antispam: BCL:0;
x-microsoft-antispam-message-info: /07cGYBxOLLKVBAaGVXZOTHj/qQwPH9nK90hTHBIdQ+S9gl/hL4bfyxxi5uRN+xDZszsforlspCz3SF84GtfuGs40WOOHgaZuDKG/30t1/ypsRFcYSAwsi6fBnKhDrtjgj2jVgBxVC7J7GbhYPPgFl1+NetljURFvWXauDv1VKK3twaMFDwJnW44Zt9dURFPf1LDpFMKqP5jmYWcEK6B/zVh9gP8VuwzShzzV5wSt8XQEbdCj6oRSV2rfkOm124bbe9OBbVTD7jkcOPVONVXQXwyw0uPKa0L6bYVQS1HmO6MlHlpOnKBhMmKgo91lfmBMvLoUaBkaCTKXWWLqKVqjVoKx7qSwf1qdVMiaKsiqXw=
x-forefront-antispam-report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:VI1PR03MB3680.eurprd03.prod.outlook.com;PTR:;CAT:NONE;SFS:(4636009)(136003)(346002)(376002)(39860400002)(396003)(366004)(6486002)(5660300002)(316002)(7116003)(83380400001)(186003)(8936002)(786003)(6506007)(36756003)(33656002)(66446008)(2616005)(86362001)(4744005)(76116006)(6916009)(66574015)(8676002)(66946007)(478600001)(66556008)(4326008)(6512007)(66476007)(64756008)(71200400001)(44832011)(91956017)(2906002)(45980500001);DIR:OUT;SFP:1101;
x-ms-exchange-transport-forked: True
Content-Type: text/plain; charset="us-ascii"
Content-ID: <6A93DBCCB0EEF8498860DB64F13F9999@eurprd03.prod.outlook.com>
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
X-OriginatorOrg: sendingdomain.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-AuthSource: VI1PR03MB3680.eurprd03.prod.outlook.com
X-MS-Exchange-CrossTenant-Network-Message-Id: c3f4160b-b9c6-444f-d45f-08d8e969c0f6
X-MS-Exchange-CrossTenant-originalarrivaltime: 17 Mar 2021 17:26:08.9885
(UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 5437e7eb-83fb-4d1a-bfd3-bb247e061bf1
X-MS-Exchange-CrossTenant-mailboxtype: HOSTED
X-MS-Exchange-CrossTenant-userprincipalname: ZipWxxH8/rQkcocxo4TQm2UgZMpINIZejK8vG80jsVXgu366SPtfLWFyYlwCxSW6Rbsj+CU+utKqNXOKtXYPLi2on82DgjFUu7sGjzCxcpo=
X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI1PR03MB6382
Reporting-MTA: dns;VI1PR03MB6382.eurprd03.prod.outlook.com
Received-From-MTA: dns;VI1PR03MB3680.eurprd03.prod.outlook.com
Arrival-Date: Wed, 17 Mar 2021 17:26:09 +0000
Final-Recipient: rfc822;inboundaddress@discoursedomain.net
Action: failed
Status: 5.1.1
Diagnostic-Code: smtp;550 5.1.1 Requested action not taken: mailbox unavailable
Remote-MTA: dns;inbound-smtp.us-east-1.amazonaws.com
X-Display-Name: inboundaddress@discoursedomain.net