public static class Constants
    {
        public static class Mail
        {
            public const string HOST = "zimbra.smartit.bg";
            public const int PORT = 25;
            public const bool USE_SSL = false;
            public const string USERNAME = "";
            public const string PASSWORD = "";
            public const string FROM = "developers@easycredit.bg";
        }
    }

public static class Mail
{
public static void SendMail(string subject, string body, string mailTo)
        {
            SmtpClient smpt = new SmtpClient(Constants.Mail.HOST, Constants.Mail.PORT);
            smpt.DeliveryMethod = SmtpDeliveryMethod.Network;

            if (!string.IsNullOrEmpty(Constants.Mail.USERNAME) && !string.IsNullOrEmpty(Constants.Mail.PASSWORD))
            {
                smpt.UseDefaultCredentials = false;
                smpt.Credentials = new NetworkCredential(Constants.Mail.USERNAME, Constants.Mail.PASSWORD);
            }

            smpt.EnableSsl = Constants.Mail.USE_SSL;

            MailMessage msg = new MailMessage(Constants.Mail.FROM, mailTo, subject, body);
            msg.IsBodyHtml = true;

            using (smpt)
            {
                smpt.Send(msg);
            }
        }
}