C# 用MimeKit/Outlook发送的电子邮件越来越少，变成了gmail'；s垃圾邮件文件夹，这是第一次

我们使用MimeKit作为SMTP客户端向用户发送电子邮件。通常，当邮件第一次到达他们的gmail帐户时，它就会落入垃圾邮件箱。然后，如果删除“垃圾邮件”标志，后续电子邮件将保留在收件箱中

在C#级有什么需要做的吗？或者在Outlook/Azure DNS级别

C#代码片段如下所示：

var message=new mimessage（）；
message.From.Add（新邮箱地址（“通知者”，smtpUser））；
message.To.Add（新邮箱地址（“用户”，收件人））；
message.Subject=Subject；
var bodyBuilder=new bodyBuilder（）{HtmlBody=html，TextBody=text}；
message.Body=bodyBuilder.ToMessageBody（）；
使用（var client=new SmtpClient（））
{
client.ServerCertificateValidationCallback=（s、c、h、e）=>true；
client.Connect（current.SmtpUrl、current.SmtpPort、SecureSocketOptions.StartTls）；
client.authenticationMechaniss.Remove（“XOAUTH2”）；
client.Authenticate（current.SmtpUser，current.SmtpPass）；
客户端。发送（消息）；
client.Disconnect（true）；
}   

gmail首次将其标记为“垃圾邮件”：

按“看起来安全”将使后续电子邮件有效，但我们需要第一封看起来安全的电子邮件

我还附上gmail上收到的全部邮件内容：

Delivered-To: jaimeolivaresfalcon@gmail.com
Received: by 2002:a0c:f08c:0:0:0:0:0 with SMTP id g12csp672696qvk;
        Wed, 4 Sep 2019 07:16:38 -0700 (PDT)
X-Received: by 2002:a9d:3b77:: with SMTP id z110mr8444689otb.93.1567606358405;
        Wed, 04 Sep 2019 07:12:38 -0700 (PDT)
X-Google-Smtp-Source: APXvYqw3m+1ZsX0fhLp8SuYRXSxfxUtUaYyLo4BZjxq+nVuni9VUHkVmOBnhBg/vThsIaIoA3chE
X-Received: by 2002:a9d:3b77:: with SMTP id z110mr8444615otb.93.1567606357487;
        Wed, 04 Sep 2019 07:12:37 -0700 (PDT)
ARC-Seal: i=2; a=rsa-sha256; t=1567606357; cv=pass;
        d=google.com; s=arc-20160816;
        b=MvKIcQqivTBGk3GqNz9MiIMtzUt4gJc0hJMoVHp7LMJyHO+AAiPfDGAdQYy7MwF0YF
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         aOkw==
ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816;
        h=mime-version:content-language:accept-language:message-id:date
         :thread-index:thread-topic:subject:to:from:dkim-signature;
        bh=LjkQ2fZg1ziyuIJx9jwPMT7LT3T4ABbJmFUMJxavtNY=;
        b=NHWmx+VtSxm9xrCGtEHdQPhCs7cF8qepGyU/uZ2MDF+dLBQygpghVzD4zwondLS0En
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         wKWdfWv9PPR/Espq66dONAgaqAcauPO35YYhMMu4ND2TCbDqmF7nPoZkf/iitGvYgL78
         1Xvw==
ARC-Authentication-Results: i=2; mx.google.com;
       dkim=pass header.i=@efferenthealthllc.onmicrosoft.com header.s=selector2-efferenthealthllc-onmicrosoft-com header.b=ETAIKEtN;
       arc=pass (i=1 spf=pass spfdomain=efferenthealth.com dkim=pass dkdomain=efferenthealth.com dmarc=pass fromdomain=efferenthealth.com);
       spf=pass (google.com: domain of notifier@efferenthealth.com designates 2a01:111:f400:fe44::629 as permitted sender) smtp.mailfrom=notifier@efferenthealth.com
Return-Path: <notifier@efferenthealth.com>
Received: from NAM02-SN1-obe.outbound.protection.outlook.com (mail-sn1nam02on0629.outbound.protection.outlook.com. [2a01:111:f400:fe44::629])
        by mx.google.com with ESMTPS id k12si10006003oiw.30.2019.09.04.07.12.37
        for <jaimeolivaresfalcon@gmail.com>
        (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128);
        Wed, 04 Sep 2019 07:12:37 -0700 (PDT)
Received-SPF: pass (google.com: domain of notifier@efferenthealth.com designates 2a01:111:f400:fe44::629 as permitted sender) client-ip=2a01:111:f400:fe44::629;
Authentication-Results: mx.google.com;
       dkim=pass header.i=@efferenthealthllc.onmicrosoft.com header.s=selector2-efferenthealthllc-onmicrosoft-com header.b=ETAIKEtN;
       arc=pass (i=1 spf=pass spfdomain=efferenthealth.com dkim=pass dkdomain=efferenthealth.com dmarc=pass fromdomain=efferenthealth.com);
       spf=pass (google.com: domain of notifier@efferenthealth.com designates 2a01:111:f400:fe44::629 as permitted sender) smtp.mailfrom=notifier@efferenthealth.com
ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=NNjokEVhuXR5/dOYj6NjeePpEmQbWt5XFctGf5IRGJuGMHAuAd9cXjCTkqduSGP3bTLRqIYjwDRthcj10zcZVudxgjhe6OB50s8KJAMpXVdh+HvGD1JoqUq2BW9M0qyOQ0YDl6Fq6F3DAWMpWNIZRPlrlaOkNaO8ifHj1okiSrThxzIxuGkzGx5iUt8/S7LOBuvzgkVWoT0NendRzvl/mB1ZQgYWcpBa+PulPlYgCTtktO1rbYZgKr5qFvJGbgBvQ1bnyZtHmZRQrA7mNegfeXrK544dGEcXs1DcFo+vNeNR53dvBWFyPCkmPpdl4+rKGRkfo/PY3B1M+D003HXuqQ==
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=LjkQ2fZg1ziyuIJx9jwPMT7LT3T4ABbJmFUMJxavtNY=; b=G0nSGcuGCOFD8gcKNWVcBAZ2EIGwicBs0yITe0iyVc+3BIm2/QUfSzcPk0+FRIKtklfUru/c/sTaag3j/6RwPp98uj+2I8k/hdLY0+72qvx595t+E+CMXSGyLmBxHYEcgIzWuckwnRdnUaeU0LwLsqKiCLV1QakRniWXnlzdKjvAXozRlHfnx/AOmyGGYUc5u1zTM5VJWmxprCL+bqEOZi1agY4A94MJK5UyW+YEOEgNEJuyx1+pgdpeQkYVqeYVAk5AcFKLgYNBLpxvW0oVqRMECOV6zlI8xJU8qiFaW64qrBQVYQF8nRfQZd8oI3nmIIoPrstNWqgEOH/UEajoNA==
ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=efferenthealth.com; dmarc=pass action=none header.from=efferenthealth.com; dkim=pass header.d=efferenthealth.com; arc=none
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=efferenthealthllc.onmicrosoft.com; s=selector2-efferenthealthllc-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=LjkQ2fZg1ziyuIJx9jwPMT7LT3T4ABbJmFUMJxavtNY=; b=ETAIKEtNCHLfnl7Fzp8XUI+NlLP/HVTzkmlFS6XwZsLZP5vOj0hJ+1KASa6mjEAvPJbmM2iDTvCMRW8UfigfVSC6hT04OyaiGjNzOjTkR8gN1TCvzNr7esQzyXR94vmz2MjLiycuhNJJMdGGRUoYZUxGhvj6F0muEBoZZ034GLQ=
Received: from BN6PR1401MB2004.namprd14.prod.outlook.com (10.174.116.149) by BN6PR1401MB1907.namprd14.prod.outlook.com (10.174.115.146) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.2220.18; Wed, 4 Sep 2019 14:12:35 +0000
Received: from BN6PR1401MB2004.namprd14.prod.outlook.com ([fe80::1de9:93da:5da7:4415]) by BN6PR1401MB2004.namprd14.prod.outlook.com ([fe80::1de9:93da:5da7:4415%11]) with mapi id 15.20.2220.022; Wed, 4 Sep 2019 14:12:35 +0000
From: Notifier <notifier@efferenthealth.com>
To: User <jaimeolivaresfalcon@gmail.com>
Subject: Notification
Thread-Topic: Notification
Thread-Index: AQHVYyrMLhjkfFeVAkmoUM8Y198VPw==
Date: Wed, 4 Sep 2019 14:12:34 +0000
Message-ID: <98UUW7B0H8U4.EB3P8CQCSUEN2@localhost.localdomain>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach: 
X-MS-TNEF-Correlator: 
x-clientproxiedby: SN4PR0401CA0034.namprd04.prod.outlook.com (2603:10b6:803:2a::20) To BN6PR1401MB2004.namprd14.prod.outlook.com (2603:10b6:405:59::21)
authentication-results: spf=none (sender IP is ) smtp.mailfrom=notifier@efferenthealth.com;
x-ms-exchange-messagesentrepresentingtype: 1
x-originating-ip: [13.84.163.72]
x-ms-publictraffictype: Email
x-ms-office365-filtering-correlation-id: 6291f624-e9b1-484f-f114-08d73141eea5
x-microsoft-antispam: BCL:0;PCL:0;RULEID:(2390118)(7020095)(4652040)(7021145)(8989299)(4534185)(7022145)(4603075)(4627221)(201702281549075)(8990200)(7048125)(7024125)(7027125)(7023125)(5600166)(711020)(4605104)(1401327)(2017052603328)(7193020);SRVR:BN6PR1401MB1907;
x-ms-traffictypediagnostic: BN6PR1401MB1907:
x-ms-exchange-purlcount: 1
x-microsoft-antispam-prvs: <BN6PR1401MB1907D7529E3B99DE63CB070DA0B80@BN6PR1401MB1907.namprd14.prod.outlook.com>
x-ms-oob-tlc-oobclassifiers: OLM:660;
x-forefront-prvs: 0150F3F97D
x-forefront-antispam-report: SFV:NSPM;SFS:(10009020)(4636009)(366004)(136003)(39830400003)(396003)(42606007)(346002)(376002)(199004)(189003)(66946007)(2906002)(3480700005)(558084003)(476003)(316002)(25786009)(486006)(256004)(508600001)(52116002)(99286004)(66556008)(7116003)(66476007)(33656002)(305945005)(71200400001)(71190400001)(66446008)(64756008)(8936002)(6486002)(7736002)(81156014)(81166006)(8676002)(6306002)(51815007)(10126004)(386003)(6506007)(53936002)(66066001)(86362001)(221733001)(9686003)(236005)(6512007)(606006)(14454004)(6916009)(6436002)(186003)(54896002)(26005)(6116002)(102836004)(3846002)(1411001)(5660300002);DIR:OUT;SFP:1101;SCL:1;SRVR:BN6PR1401MB1907;H:BN6PR1401MB2004.namprd14.prod.outlook.com;FPR:;SPF:None;LANG:en;PTR:InfoNoRecords;A:3;MX:1;
received-spf: None (protection.outlook.com: efferenthealth.com does not designate permitted sender hosts)
x-ms-exchange-senderadcheck: 1
x-microsoft-antispam-message-info: bHkvE3Co8At1/X9BzBqbqZFNCIBAppNhqQqCJDoMByjqBv9VGO25sOpCKS8OSh1obZBR1t5nvkdn0CFuuFoGjhwNaXt7MakSQfeS8auVa0d/GUpLb7Y3oJ8Xm2az23Z4+l3YP4ITa5Fhd8DxliNV8JO4ZYDxC6uG3Gh8my4MewFPQScRgUgx49un88gu8zK3MDyUhxIlYB1WjdqPPG3xtQMIBHbA4EuPFa5Is2Jk7D4PsMjrpTvL8GyZVYhgVWC71OrwG7C575IB1XIanF7woc0VZxBlAjh1xY8gaUDYuT7Lc1b/cSKcyUjOG7J0XR8ilS4fp86IaGeKdivi4h2MJ8oqW+A9obH2+GW5NTpBMgvYE7zFNBQhxuuC/jxny7F2zs4z5vacC0HOXeUwgfOLWZsUdZC2SDW6HjXkw0TejIA=
x-ms-exchange-transport-forked: True
Content-Type: multipart/alternative; boundary="_000_98UUW7B0H8U4EB3P8CQCSUEN2localhostlocaldomain_"
MIME-Version: 1.0
X-OriginatorOrg: efferenthealth.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 6291f624-e9b1-484f-f114-08d73141eea5
X-MS-Exchange-CrossTenant-originalarrivaltime: 04 Sep 2019 14:12:34.9389 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 02ecab7f-85de-4d13-9c86-db5eefd90ee2
X-MS-Exchange-CrossTenant-mailboxtype: HOSTED
X-MS-Exchange-CrossTenant-userprincipalname: zj/y6ItrIybuyjEREqOxS6sBThdrcjGbcWxxKICSNnb1h2GZnVz0UsJO0Kcp51LYMrFzeRKKgbFFnJPNgXa2GoLY5CBVrkaMzJbHf0oywnA=
X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN6PR1401MB1907

--_000_98UUW7B0H8U4EB3P8CQCSUEN2localhostlocaldomain_
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: base64

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--_000_98UUW7B0H8U4EB3P8CQCSUEN2localhostlocaldomain_
Content-Type: text/html; charset="utf-8"
Content-ID: <28HFX7B0H8U4.5CY7IBFO17VC@localhost.localdomain>
Content-Transfer-Encoding: base64

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cmU8L2E+DQo8L2JvZHk+DQo8L2h0bWw+DQo=
--_000_98UUW7B0H8U4EB3P8CQCSUEN2localhostlocaldomain_--

交付给：jaimeolivaresfalcon@gmail.com
收到：截止2002年：a0c:f08c:0:0:0:0，SMTP id为g12csp672696qvk；
2019年9月4日星期三07:16:38-0700（太平洋时间）
X-Received:by 2002:a9d:3b77:：SMTP id为z110mr8444689otb.93.156760358405；
2019年9月4日星期三07:12:38-0700（太平洋时间）
X-Google-Smtp-Source:APXvYqw3m+1ZSX0FHLP8SUYRXSXFXUTUAAYYLO4BZJXQ+nVuni9VUHkVmOBnhBg/VTHSIAIO3CHE
X-Received:by 2002:a9d:3b77:：SMTP id为z110mr8444615otb.93.156760357487；
2019年9月4日星期三07:12:37-0700（太平洋时间）
电弧密封：i=2；a=rsa-sha256；t=156760357；cv=通过；
d=google.com；s=arc-20160816；
b=MvKIcQqivTBGk3GqNz9MiIMtzUt4gJc0hJMoVHp7LMJyHO+AAiPfDGAdQYy7MwF0YF
QRM1VKQL5F2DMC3UKGYSZLDFK6A4XWBFQKQSQOTZCQ7ZHK3RUSUOTIAO6A2FDN6NIKZ
cUY+92Y0+hOpu0MF/bGYCfy+3+NCJXOUOVLCGNWUAFRLVYQOIQ0LESIQT4MSOOCU1GD
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jffxtMeD0h+OPBMATBAS9UAO7RCJD5LQXSurtby7PJTBYMAKC82O2xK3R1QSWIGWCPI
aOkw==
ARC报文签名：i=2；a=rsa-sha256；c=放松/放松；d=google.com；s=arc-20160816；
h=mime版本：内容语言：接受语言：消息id:日期
：线程索引：线程主题：主题：收件人：发件人：dkim签名；
bh=LjkQ2fZg1ziyuIJx9jwPMT7LT3T4ABbJmFUMJxavtNY=；
b=NHWmx+VtSxm9xrCGtEHdQPhCs7cF8qepGyU/uZ2MDF+dLBQygpghVzD4zwondLS0En
CpV/xfSbzx5aRLTnEq3468awqMnPRTmxjT3X/m3VLcq8sSg43ZtJLr5dxlUX2Eyt5Chu
v4bnC+0wQM05OCMQkTayCWEE/LL8AQKCJYDUK6WD4VU2CSBUZIEDXCZF/ysnodrhWgx
VgVLAA4至4RWWBBE6N2C9LSA3xO8JU+6F4YS1TTHDPLJVD/WR7VTHAU54EH/UQ3e
wKWdfWv9PPR/ESPQ66Donagaqacaupo35YYHMMU4ND2TCDBQMF7NPOZKF/iitGvYgL78
1Xvw==
ARC认证结果：i=2；mx.google.com；
dkim=passheader.i=@efferenthealthlc.onmicrosoft.com header.s=selector2 efferenthealthlc onmicrosoft com header.b=ETAIKEtN；
arc=pass（i=1 spf=pass spfdomain=efferenthealth.com dkim=pass dkddomain=efferenthealth.com dmarc=pass fromdomain=efferenthealth.com）；
spf=pass（google.com:domain of ofnotifier@efferenthealth.com将2a01:111:f400:fe44:：629指定为允许的发件人）smtp.mailfrom=notifier@efferenthealth.com
返回路径：
收到：来自NAM02-SN1-obe.outbound.protection.outlook.com（邮件-sn1nam02on0629.outbound.protection.outlook.com。[2a01:111:f400:fe44:：629]）
由mx.google.com提供，ESMTPS id为k12si10006003oiw.30.2019.09.04.07.12.37
对于
（版本=TLS1_2密码=ECDHE-RSA-AES128-SHA位=128/128）；
2019年9月4日星期三07:12:37-0700（太平洋时间）
收到SPF:pass（google.com:domain of ofnotifier@efferenthealth.com将2a01:111:f400:fe44:：629指定为允许的发送方）客户端ip=2a01:111:f400:fe44:：629；
认证结果：mx.google.com；
dkim=passheader.i=@efferenthealthlc.onmicrosoft.com header.s=selector2 efferenthealthlc onmicrosoft com header.b=ETAIKEtN；
arc=pass（i=1 spf=pass spfdomain=efferenthealth.com dkim=pass dkddomain=efferenthealth.com dmarc=pass fromdomain=efferenthealth.com）；
spf=pass（google.com:domain of ofnotifier@efferenthealth.com将2a01:111:f400:fe44:：629指定为允许的发件人）smtp.mailfrom=notifier@efferenthealth.com
电弧密封：i=1；a=rsa-sha256；s=arcselector9901；d=微软网站；cv=无；（2）b（2）b（2）b（2）b（2）b（2）b（2）b（2）b（2）b（2）b（2）b（2）b（2）b）b（2）b）b（2）b）b（2）b）b（2）b（2）b（2）b（2）b）b（2）b）b（2）b）b（2）b）b（2）b）b（2）b）b（2）b（2）b（2）b）b（2）b）b（2）b）b（2）b）b）b）b（2）b（2）b（2）b）b）b（2）b）b）b）b（2）b（2）b）b）b（2）b）b）b）b）b）b（2）b）b）b）b）b（2）b）b）b）b）b（2）b）b）b）HXUQQ==
ARC报文签名：i=1；a=rsa-sha256；c=放松/放松；d=微软网站；s=arcselector9901；h=From:Date:Subject:Message ID:Content Type:MIME Version:X-MS-Exchange-SenderADCheck；bh=LjkQ2fZg1ziyuIJx9jwPMT7LT3T4ABbJmFUMJxavtNY=；2）2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 Miioprstnwqgeoh/UEajoNA==
ARC认证结果：i=1；mx.microsoft.com 1；spf=passSMTP.mailfrom=efferenthealth.com；dmarc=pass action=none header.from=efferenthealth.com；dkim=passheader.d=efferenthealth.com；弧=无
DKIM签名：
foreach (var part in message.BodyParts.OfType<TextPart> ())
    part.ContentTransferEncoding = ContentEncoding.QuotedPrintable;

message.MessageId = MimeUtils.GenerateMessageId ("efferenthealthllc.onmicrosoft.com");

foreach (var part in message.BodyParts.OfType<TextPart> ())
    part.ContentId = null;