I want to make a web application to sending mail [closed]
using System.Net.Mail;
using System.Net;

SmtpClient mailClient = new SmtpClient("smtp.gmail.com", "587");
mailClient.EnableSsl = true;
mailClient.Credentials = new NetworkCredential("gmail_username", "gmail_password");
mailClient.Send("from@gmail.com",
                "to@gmail.com",
                "subject goes here",
                "email body goes here");

MailMessage message = new MailMessage();
message.From = new MailAddress("sender@foo.bar.com");
message.To.Add(new MailAddress("recipient1@foo.bar.com"));
message.CC.Add(new MailAddress("carboncopy@foo.bar.com"));

message.Subject = "This is my subject";
message.Body = "This is the content";

SmtpClient client = new SmtpClient();
client.Send(message);

<system.net>
    <mailSettings>
      <smtp from="test@foo.com">
        <network host="smtpserver1" port="25" userName="username" password="secret" defaultCredentials="true" />
      </smtp>
    </mailSettings>
</system.net>