使用 Java Mail for Office 365 时出现异常

Question

我在通过 Windows Server 中的应用程序使用 Office365 Exchange 服务器的 Java Mail 发送邮件时遇到以下异常。 Windows服务器位于云平台。与我们的应用程序相同的配置（Exchange 服务器详细信息）正在 Windows 11 个人笔记本电脑和另一个 Windows 服务器（位于不同的云供应商）中运行。

org.springframework.mail.MailSendException: Mail server connection failed; nested exception is javax.mail.MessagingException: Unknown SMTP host: smtp.office365.com;
  nested exception is:
    java.net.UnknownHostException: smtp.office365.com. Failed messages: javax.mail.MessagingException: Unknown SMTP host: smtp.office365.com;
  nested exception is:
    java.net.UnknownHostException: smtp.office365.com; message exception details (1) are:
Failed message 1:
javax.mail.MessagingException: Unknown SMTP host: smtp.office365.com;
  nested exception is:
    java.net.UnknownHostException: smtp.office365.com
    at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1959)
    at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:654)
    at javax.mail.Service.connect(Service.java:295)
    at org.springframework.mail.javamail.JavaMailSenderImpl.connectTransport(JavaMailSenderImpl.java:518)
    at org.springframework.mail.javamail.JavaMailSenderImpl.doSend(JavaMailSenderImpl.java:437)
    at org.springframework.mail.javamail.JavaMailSenderImpl.send(JavaMailSenderImpl.java:361)
    at org.springframework.mail.javamail.JavaMailSenderImpl.send(JavaMailSenderImpl.java:356)
    at com.grc.jframework.mail.FailsafeMailSender.sendInternal(FailsafeMailSender.java:146)
    at com.grc.jframework.mail.FailsafeMailSender.lambda$init$0(FailsafeMailSender.java:115)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)
Caused by: java.net.UnknownHostException: smtp.office365.com
    at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
    at java.net.PlainSocketImpl.connect(Unknown Source)
    at java.net.SocksSocketImpl.connect(Unknown Source)
    at java.net.Socket.connect(Unknown Source)
    at java.net.Socket.connect(Unknown Source)
    at com.sun.mail.util.SocketFetcher.createSocket(SocketFetcher.java:321)
    at com.sun.mail.util.SocketFetcher.getSocket(SocketFetcher.java:237)
    at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1927)
    ... 11 more

Windows Server 端有什么需要更改/更新的配置吗？

以下是 SMTP 服务器详细信息：

smtp.发件人.主端口 = 587

smtp.sender.reserve.auth_type = 匿名

smtp.sender.main.auth_type = TLS

smtp.sender.main.host = smtp.office365.com

smtp.发件人.保留端口 = 25

smtp.sender.main.timeout_sec = 90

Answer 1

正如 @Mark Rotteveel 在评论中建议的那样，这是 smtp.office365.com DNS 的问题，并已由管理团队解决。