java 服务器发送邮件失败,在Java中发送邮件时出现错误-优快云博客

本文档描述了尝试使用Java通过ISP提供商的SMTP服务器发送邮件时遇到的错误。问题在于代码在本地工作正常，但在上传到服务器后抛出了`javax.mail.MessagingException`，伴随着`SSLException: Unrecognized SSL message, plaintext connection?`。作者尝试禁用SSL并设置非SSL连接属性，但问题仍然存在。博客内容详细列出了代码示例和堆栈跟踪，寻求解决方案。

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I was trying to send mail using java. The code i was using worked when I used it with GMail's SMTP server ("smtp.gmail.com"). But when I changed the code (smtp_host_name, smtp_port properties and authentication UserID/Pwd) to send email through the SMTP server of my ISP provider, this code failed.

Here is my code-

String host = "smtp server host of my isp provider";

Properties props = System.getProperties();

props.put("mail.smtp.host", host);

props.put("mail.debug", "true");

props.put("mail.transport.protocol.", "smtp");

props.put("mail.smtp.auth", "true");

props.put("mail.smtp.port", "25");

props.put("mail.smtp.starttls.enable","true");

Session mailSession = Session.getDefaultInstance(props, null);

mailSession.setDebug(sessionDebug);

Message msg = new MimeMessage(mailSession);

msg.setFrom(new InternetAddress(from));

InternetAddress[] address = {new InternetAddress(to)};

msg.setRecipients(Message.RecipientType.TO, address);

msg.setSubject(subject);

msg.setContent(messageText, "text/html");

Transport transport = mailSession.getTransport("smtp");

transport.connect(host, user, pass);

And i am getting this error-

javax.mail.MessagingException: Exception reading response;

nested exception is: javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection?

The problem is i am able to send mails from the same code from my system workspace. But after i upload the war file to host, i get the above error. I think i disabled SSL but still getting this error. Can someone please help. Its urgent...

I followed the steps given below but still i am getting the same error.

Here is my code now-

String host = "mail.myweb.com", user = emailUser, pass = emailPasswd;

String to = emailID;

String from = emailFrom;

String subject = subj;

String messageText = message;

boolean sessionDebug = true;

Properties props = System.getProperties();

props.put("mail.smtp.host", host);

props.put("mail.debug", "true");

props.put("mail.transport.protocol", "smtp");

props.put("mail.smtp.auth", "true");

props.put("mail.smtp.port", "25");

Session mailSession = Session.getDefaultInstance(props, null);

mailSession.setDebug(sessionDebug);

Message msg = new MimeMessage(mailSession);

msg.setFrom(new InternetAddress(from));

InternetAddress[] address = {new InternetAddress(to)};

msg.setRecipients(Message.RecipientType.TO, address);

msg.setSubject(subject);

msg.setContent(messageText, "text/html");

Transport transport = mailSession.getTransport("smtp");

transport.connect(host, user, pass);

try {

transport.sendMessage(msg, msg.getAllRecipients());

}

catch (Exception e) {

System.out.println("Error" + e.getMessage());

}

transport.close();

}

Here is the full stacktrace

javax.mail.MessagingException: Exception reading response; nested exception is: javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection?

com.sun.mail.smtp.SMTPTransport.readServerResponse(SMTPTransport.java:1611)

com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1369)

com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:412)

javax.mail.Service.connect(Service.java:288)

javax.mail.Service.connect(Service.java:169)

common.sendMail.(sendMail.java:35)

frontend.reply.sendfeedback(reply.java:74)

sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)

sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)

java.lang.reflect.Method.invoke(Method.java:597)

com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:441)

com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:280)

com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:243)

com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:165)

com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)