无法连接到james服务器本地主机

Question

我正在尝试连接到James服务器本地主机，但出现异常

javax.mail.MessagingException: Could not connect to SMTP host: localhost, port:25;
 nested exception is:
            java.net.SocketException: Network is unreachable: connect
            at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1545)
            at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:453)
            at javax.mail.Service.connect(Service.java:313)      
            at javax.mail.Service.connect(Service.java:172) 
            at javax.mail.Service.connect(Service.java:121) 
            at javax.mail.Transport.send0(Transport.java:190)
            at javax.mail.Transport.send(Transport.java:120)
            at mail.main(mail.java:78)
    Caused by: java.net.SocketException: Network is unreachable: connect
            at java.net.PlainSocketImpl.socketConnect(Native Method)
            at java.net.PlainSocketImpl.doConnect(Unknown Source)
            at java.net.PlainSocketImpl.connectToAddress(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:267)
            at com.sun.mail.util.SocketFetcher.createSocket(SocketFetcher.java:227)
            at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1511)
            ... 7 more

我的James Server的目录结构是：

C:\apache-james-2.3.2
|
|
|
|------C:\apache-james-2.3.2\james-2.3.2
|
|------C:\apache-james-2.3.2\javamail-1.4.2
|
|------C:\apache-james-2.3.2\jaf-1.0.2

这是代码，它引发异常：

我没有更改james-2.3.2子目录的配置文件中的任何内容，所以我为什么得到那个例外？

这是代码，它引发异常：

// imports omitted
public class mail {
    public static void main(String[] args) {
        String to = "blue@localhost";
        String from = "red@localhost";
        String subject = "Hello";
        String body = "What's up";
        if ((from != null) && (to != null) && (subject != null) && (body != null)) {
            try { // we have mail to send
                Properties props = new Properties();
                props.put("mail.host", "localhost");
                props.put("mail.smtp.auth", "true");
                props.put("mail.debug", "true");
                Session session = Session.getInstance(props, new javax.mail.Authenticator() {
                    protected PasswordAuthentication getPasswordAuthentication() {
                        return new PasswordAuthentication("red", "red");
                    }
                });
                Message message = new MimeMessage(session);
                message.setFrom(new InternetAddress(from));
                Address[] add = { new InternetAddress(to) };
                message.setRecipients(Message.RecipientType.TO, add);
                message.setSubject(subject);
                message.setContent(body, "text/plain");
                message.setText(body);
                Transport.send(message);
                System.out.println(" Your message to " + to + " was successfully sent.");
            } catch (Throwable t) {
                t.printStackTrace();
            }
        }
    }
}

Answer 1

例外是说本地主机不可访问。我希望您的计算机没有正确配置其回送网络地址（localhost / 127.0.0.1）。

编辑：我假设您正在同一台计算机上运行客户端和服务器。如果不是，则不能使用localhost / 127.0.0.1。

Answer 2

我总是尝试远程登录到邮件主机上的端口25，以检查是否可以访问服务器。尝试连接到127.0.0.1，以检查James是否接受传入的连接。我想您已经检查了詹姆斯的日志中是否有错误？

Answer 3

尝试使用IP地址127.0.0.1代替主机名'localhost'-可能在您的计算机上未正确设置DNS查找，因此它不知道名称'localhost'意味着什么。

打开文件C:\Windows\System32\drivers\etc\hosts，并确保它包含这样的行：

127.0.0.1       localhost

也请尝试关闭防火墙或防病毒软件。

Answer 4

• 尝试以Linux的root用户身份启动apache james或以Windows上的管理员。并检查服务器是否成功是否在日志文件夹中的james-server.log文件上启动了

• 在主机文件中添加主机名

  127.0.0.1       localhost
  

• 已放置文件

  on linux /etc/hosts
  on windows C:\Windows\System32\drivers\etc\hosts
  

• 并重新启动服务器。