外发电子邮件被标记为垃圾邮件：BAYES_99

Question

我正在开发一个网络应用程序。
所有发出的电子邮件都被标记为垃圾邮件，或者被收件人的电子邮件提供商完全拒绝。
这会阻止我们向注册用户发送欢迎电子邮件、激活码或其他任何内容。

我使用 isnotspam.com 测试了电子邮件发送，问题似乎出在 BAYES_99 和 BAYES_999 指标上。无论电子邮件内容如何，​​都会发生这种情况。

有人能告诉我为什么会发生这种情况吗？有没有办法使外发电子邮件不被垃圾邮件过滤器标记为垃圾邮件？

这是 isnotspam.com 测试结果（为了隐私我修改了一些参数）。

    This message is an automatic response from isNOTspam's authentication verifier service. The service allows email senders to perform a simple check of various sender authentication mechanisms. It is provided free of charge, in the hope that it is useful to the email community. While it is not officially supported, we welcome any feedback you may have at .

    Thank you for using isNOTspam.

    The isNOTspam team

    ==========================================================
    Summary of Results
    ==========================================================

    SPF Check : pass
    Sender-ID Check : pass
    DomainKeys Check : neutral
    DKIM Check : pass
    SpamAssassin Check : ham (non-spam)
    ==========================================================
    Details:
    ==========================================================

    HELO hostname: my.hostname.com
    Source IP: XX.YY.WW.ZZ
    mail-from: service@mydomain.com
    Anonymous To: ins-3mqqpdgw@isnotspam.com
    ---------------------------------------------------------
    SPF check details:
    ----------------------------------------------------------

    Result: pass
    ID(s) verified: smtp.mail=service@mydomain.com
    DNS record(s):
    mydomain.com.    11379   IN      TXT     "v=spf1 +a +mx +ip4:XX.YY.WW.ZZ +ip4:AA.BB.CC.DD +include:_spf.google.com ~all"


    ----------------------------------------------------------
    Sender-ID check details:
    ----------------------------------------------------------

    Result: pass

    ID(s) verified: smtp.mail=service@mydomain.com
    DNS record(s):
    mydomain.com.    11379   IN      TXT     "v=spf1 +a +mx +ip4:XX.YY.WW.ZZ +ip4:AA.BB.CC.DD +include:_spf.google.com ~all"


    ----------------------------------------------------------
    DomainKeys check details:
    ----------------------------------------------------------

    Result: neutral (message not signed)
    ID(s) verified: header.From=service@mydomain.com
    Selector=
    domain=
    DomainKeys DNS Record=

    ----------------------------------------------------------
    DKIM check details:
    ----------------------------------------------------------

    Result: pass
    ID(s) verified: header.From=service@mydomain.com
    Selector=default
    domain=mydomain.com

    DomainKeys DNS Record=default._domainkey.mydomain.com


    ----------------------------------------------------------
    SpamAssassin check details:
    ----------------------------------------------------------
    SpamAssassin 3.4.1 (2015-04-28)

    Result: ham (non-spam) (03.7points, 10.0 required)

    pts rule name description
    ---- ---------------------- -------------------------------


    * 3.5 BAYES_99 BODY: Bayes spam probability is 99 to 100%
    * [score: 1.0000]
    * 0.0 URIBL_BLOCKED ADMINISTRATOR NOTICE: The query to URIBL was blocked.
    * See http://wiki.apache.org/spamassassin/DnsBlocklists#dnsbl-block
    * for more information.
    * [URIs: mydomain.com]
    * -0.0 SPF_HELO_PASS SPF: HELO matches SPF record
    * -0.0 SPF_PASS SPF: sender matches SPF record
    * 0.2 BAYES_999 BODY: Bayes spam probability is 99.9 to 100%
    * [score: 1.0000]
    * 0.1 HTML_MESSAGE BODY: HTML included in message
    * -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's
    * domain
    * -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature
    * 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily
    * valid
    X-Spam-Status: Yes, hits=3.7 required=-20.0 tests=BAYES_99,BAYES_999,
    DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HTML_MESSAGE,SPF_HELO_PASS,SPF_PASS,
    URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.1
    X-Spam-Score: 3.7

Answer 1

在 spamassassin 中查找垃圾邮件的统计方法我不是统计学家，但您可以通过 spamassassin 的官方文档找到您的回复以及此回复：SpamAssassin 如何定义 BAYES_99 ？如何避免呢？

https://wiki.apache.org/spamassassin/Rules/BAYES_99

https://en.wikipedia.org/wiki/Naive_Bayes_spam_filtering