The SmtpClient class in the System.Net.Mail namespace allows you to send mail messages through the Simple Mail Transfer Protocol.
To send a simple text message, instantiate SmtpClient, set its Host property to your SMTP server address, and then call Send:
using System;
using System.Net;
using System.Net.Mail;
using System.Threading;
using System.IO;
using System.Text;
class ThreadTest
{
static void Main()
{
SmtpClient client = new SmtpClient();
client.Host = "mail.myisp.net";
client.Send("from@adomain.com", "to@adomain.com", "subject", "body");
}
}