c# - 当我运行这段代码时，它在 (smtp.Send(mm);) 出现错误，我不知道如何解决

Question

这段代码在运行时给我带来了一些问题。它不发送消息，它说错误在 smtp.Send(mm);我无法解决它

    if (!string.IsNullOrEmpty(password))
    {
        System.Net.Mail.MailMessage mm = new System.Net.Mail.MailMessage("eden.elao@gmail.com", Username.Text.Trim());
        mm.Subject = "Password Recovery";
        mm.Body = string.Format("Hi {0},<br /><br />Your password is {1}.<br /><br />Thank You.", username, password);
        mm.IsBodyHtml = true;
        System.Net.Mail.SmtpClient smtp = new System.Net.Mail.SmtpClient();
        smtp.Host = "smtp.gmail.com";
        smtp.EnableSsl = true;
        System.Net.NetworkCredential NetworkCred = new System.Net.NetworkCredential();
        NetworkCred.UserName = "sender@gmail.com";
        NetworkCred.Password = "<Password>";
        smtp.UseDefaultCredentials = true;
        smtp.Credentials = NetworkCred;
        smtp.Port = 587;
        smtp.Send(mm); // the error is here.
        lblMessage.ForeColor = System.Drawing.Color.Green;
        lblMessage.Text = "Password has been sent to your email address.";
    }
    else
    {
        lblMessage.ForeColor = System.Drawing.Color.Red;
        lblMessage.Text = "This email address does not match our records.";
    }
}

Answer 1

我相信您遇到了 smtp 服务器的安全问题，我通过在这些行中提供我的真实 gmail 帐户信息使其正常工作:"<Password>"似乎行不通。

  NetworkCred.UserName = "myEmail@gmail.com";
  NetworkCred.Password = "myPassword";

并打开我的 gmail 帐户的设置以允许安全性较低的应用程序访问它。

仅供引用，对于其他人来说，这是我更改之前的错误。

Additional information: The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.5.1 Authentication Required. Learn more at