How to send email in ASP.NET C#

Just go through the below code.

SmtpClient smtpClient = new SmtpClient("mail.MyWebsiteDomainName.com", 25);

smtpClient.Credentials = new System.Net.NetworkCredential("[email protected]", "myIDPassword");
// smtpClient.UseDefaultCredentials = true; // uncomment if you don't want to use the network credentials
smtpClient.DeliveryMethod = SmtpDeliveryMethod.Network;
smtpClient.EnableSsl = true;
MailMessage mail = new MailMessage();

//Setting From , To and CC
mail.From = new MailAddress("info@MyWebsiteDomainName", "MyWeb Site");
mail.To.Add(new MailAddress("info@MyWebsiteDomainName"));
mail.CC.Add(new MailAddress("[email protected]"));

smtpClient.Send(mail);

Try using this code instead. Note: In the "from address" give your correct email id and password.

protected void btn_send_Click(object sender, EventArgs e)
{

    System.Net.Mail.MailMessage mail = new System.Net.Mail.MailMessage();
    mail.To.Add("to gmail address");
    mail.From = new MailAddress("from gmail address", "Email head", System.Text.Encoding.UTF8);
    mail.Subject = "This mail is send from asp.net application";
    mail.SubjectEncoding = System.Text.Encoding.UTF8;
    mail.Body = "This is Email Body Text";
    mail.BodyEncoding = System.Text.Encoding.UTF8;
    mail.IsBodyHtml = true;
    mail.Priority = MailPriority.High;
    SmtpClient client = new SmtpClient();
    client.Credentials = new System.Net.NetworkCredential("from gmail address", "your gmail account password");
    client.Port = 587;
    client.Host = "smtp.gmail.com";
    client.EnableSsl = true;
    try
    {
        client.Send(mail);
        Page.RegisterStartupScript("UserMsg", "<script>alert('Successfully Send...');if(alert){ window.location='SendMail.aspx';}</script>");
    }
    catch (Exception ex)
    {
        Exception ex2 = ex;
        string errorMessage = string.Empty;
        while (ex2 != null)
        {
            errorMessage += ex2.ToString();
            ex2 = ex2.InnerException;
        }
        Page.RegisterStartupScript("UserMsg", "<script>alert('Sending Failed...');if(alert){ window.location='SendMail.aspx';}</script>");
    }
}

You can try this using hotmail like this:-

MailMessage o = new MailMessage("From", "To","Subject", "Body");
NetworkCredential netCred= new NetworkCredential("Sender Email","Sender Password");
SmtpClient smtpobj= new SmtpClient("smtp.live.com", 587); 
smtpobj.EnableSsl = true;
smtpobj.Credentials = netCred;
smtpobj.Send(o);