带有 ASP.net 错误的 SMTP 邮件 5.5.1 需要身份验证

Question

美好的一天，我是使用 ASP.net 和 SMTP Mailer

的初学者

这是我的问题，我从本地发送电子邮件时总是遇到此错误并在网上搜索并尝试了解决方案，但并不那么幸运，我希望有人指出我需要什么代码以及我在哪里遇到这个错误

Message = "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"

这是我的代码：

protected void btnSendEmail_Click(object sender, EventArgs e)
        {
            // System.Web.Mail.SmtpMail.SmtpServer is obsolete in 2.0
            // System.Net.Mail.SmtpClient is the alternate class for this in 2.0
            SmtpClient smtpClient = new SmtpClient();
            MailMessage message = new MailMessage();

            try
            {
                MailAddress fromAddress = new MailAddress(txtEmail.Value, txtName.Value);
                smtpClient.Credentials = new System.Net.NetworkCredential("myUser@gmail", "password");
                // You can specify the host name or ipaddress of your server
                // Default in IIS will be localhost 
                smtpClient.Host = "smtp.gmail.com";
                smtpClient.EnableSsl = true;
                //Default port will be 25
                smtpClient.Port = 25;
                smtpClient.UseDefaultCredentials = false;
                //From address will be given as a MailAddress Object
                message.From = fromAddress;

                // To address collection of MailAddress
                message.To.Add("myEmail@gmail.com");
                message.Subject = txtSubject.Value;

                // CC and BCC optional
                // MailAddressCollection class is used to send the email to various users
                // You can specify Address as new MailAddress("admin1@yoursite.com")
                message.CC.Add("myEmail@gmail.com");

                // You can specify Address directly as string
                message.Bcc.Add(new MailAddress("myEmail@gmail.com"));

                //Body can be Html or text format
                //Specify true if it  is html message
                message.IsBodyHtml = false;

                // Message body content
                message.Body = txtaMessage.Value;
                message.BodyEncoding = System.Text.Encoding.UTF8;
                message.HeadersEncoding = System.Text.Encoding.UTF8;
                // Send SMTP mail
                smtpClient.Send(message);

                lblSuccess.Text = "Email successfully sent.";
            }
            catch (Exception ex)
            {
                lblSuccess.Text = "Send Email Failed.";
            }
        }

Answer 1

试试这个参考资料ASP Simple SMTP for C# and VB它对我可能遇到的 smtp 问题有很大帮助

Answer 2

请查看 google 支持团队，了解他们对从应用程序发送邮件的看法。 https://support.google.com/mail/answer/78775?hl=en

另外关注link可以帮到你。

Gmail Error :The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.5.1 Authentication Required

Answer 3

我试图制作一个简单的发送电子邮件的代码，试试这个

MailMessage mm = new MailMessage(); mm.From = new MailAddress("fromEmail"); mm.To.Add("toEmail"); mm.CC.Add("ccEmail"); mm.Subject = "StringSubject"; mm.Body = "BodySubject"; mm.IsBodyHtml = true; SmtpClient smtp = new SmtpClient(); smtp.Host = "smtp.gmail.com"; smtp.EnableSsl = true; System.Net.NetworkCredential NetworkCred = new System.Net.NetworkCredential(); NetworkCred.UserName = "UsernameString"; NetworkCred.Password = "PasswordString"; smtp.UseDefaultCredentials = true; smtp.Credentials = NetworkCred; smtp.Port = 587; try { smtp.Send(mm); } catch (Exception) { }

Answer 4

转到 Gmail 帐户，然后 select 连接的应用程序和网站允许安全性较低的应用程序：开（如果关闭，您将无法通过应用程序或您的网站发送邮件）

带有 ASP.net 错误的 SMTP 邮件 5.5.1 需要身份验证

SMTP Mail with ASP.net Error 5.5.1 Authentication Required

c#

asp.net

email

asp.net-mvc

smtp