using (var client = new SmtpClient())
{
client.DeliveryMethod = SmtpDeliveryMethod.SpecifiedPickupDirectory;
client.PickupDirectoryLocation = @"C:temp";
var message = new MailMessage();
message.To.Add(new MailAddress("alice@a.com"));
message.From = new MailAddress("bob@b.com");
message.Subject = "Smtp Dot Stuffing Test";
message.Body = ".A.B.C..... .0.1.2.3.4.5.6.7.8.9";
client.Send(message);
}