I think you could use this
public void SendEmail(string to)
{
SmtpClient smtp = new SmtpClient("ServerAddress", 25);//using default port 25
smtp.Credentials = new NetworkCredential("user","pass");
//user and pass should be encrypted
MailMessage mail = new MailMessage();
mail.From = "from@test.com"
mail.To = to;
mail.Subject = "Some Subject";
mail.Body="Some Body";
try
{
smtp.Send(mail);
}
catch(Exception e)
{
//do something
}
}