使用 gmail smtp 服务器发送电子邮件

Question

我一直在尝试使用以下代码从 Gmail 帐户向 gmail 帐户发送邮件。

using (MailMessage mm = new MailMessage(txtEmail.Text, txtTo.Text))
{
    mm.Subject = txtSubject.Text;
    mm.Body = txtBody.Text;
    if (fuAttachment.HasFile)
    {
        string FileName = Path.GetFileName(fuAttachment.PostedFile.FileName);
        mm.Attachments.Add(new Attachment(fuAttachment.PostedFile.InputStream, FileName));
    }
    mm.IsBodyHtml = false;
    SmtpClient smtp = new SmtpClient();
    smtp.Host = "smtp.gmail.com";
    smtp.EnableSsl = true;
    NetworkCredential NetworkCred = new NetworkCredential(txtEmail.Text, txtPassword.Text);
    smtp.UseDefaultCredentials = true;
    smtp.Credentials = NetworkCred;
    smtp.Port = 587;
    smtp.Send(mm);
    ClientScript.RegisterStartupScript(GetType(), "alert", "alert('Email sent.');", true);
}

执行到“smtp.Send(mm)”后，浏览器说正在等待，2 分钟后我收到异常消息“发送电子邮件失败”

还有下面的错误信息

连接尝试失败，因为连接方在一段时间后没有正确响应，或者连接失败，因为连接的主机没有响应。。.:587"（某些 IP）

我为此搜索了很多，但没有找到解决方案。请帮我解决这个问题。

谢谢。

Answer 1

我有过类似的尝试，但使用的是 Java。经过大量搜索后，我没有成功。然后我用了雅虎！ SMTP，它很容易工作。也许你可以试试。

Answer 2

首先，我认为你应该使用

UseDefaultCredentials = false;

和

smtp.DeliveryMethod = SmtpDeliveryMethod.Network

您还需要allow less secure apps to access your account

Answer 3

试试这个。

public static string SendMail(string stHtmlBody, string stSubject, string stToEmailAddresses)
{
    string stReturnText = string.Empty;
    try
    {
        if (!string.IsNullOrEmpty(stToEmailAddresses))
        {
            //Set SmtpClient to send Email
            string stFromUserName = "fromusername";
            string stFromPassword ="frompassword";
            int inPort = Convert.ToInt32(587);
            string stHost = "smtp.gmail.com";
            bool btIsSSL =true;



            MailAddress to = new MailAddress(stToEmailAddresses);
            MailAddress from = new MailAddress("\"" + "Title" + "\" " + stFromUserName);

            MailMessage objEmail = new MailMessage(from, to);
            objEmail.Subject = stSubject;
            objEmail.Body = stHtmlBody.ToString();
            objEmail.IsBodyHtml = true;
            objEmail.Priority = MailPriority.High;


            SmtpClient client = new SmtpClient();
            System.Net.NetworkCredential auth = new System.Net.NetworkCredential(stFromUserName, stFromPassword);
            client.Host = stHost;
            client.Port = inPort;
            client.UseDefaultCredentials = false;
            client.Credentials = auth;
            client.EnableSsl = btIsSSL;
            client.Send(objEmail);

            return stReturnText;
        }
    }
    catch (Exception ex)
    {

    }

    return stReturnText;
}