在vs2005中发送邮件的方法如下：

           System.Net.Mail.SmtpClient client = new SmtpClient();
            client.Host = "smtp.163.com";
            client.UseDefaultCredentials = false;
            client.Credentials = new System.Net.NetworkCredential("你的163用户名", "*****");
            //星号改成自己邮箱的密码
            client.DeliveryMethod = SmtpDeliveryMethod.Network;

            System.Net.Mail.MailMessage message = new MailMessage("你的163邮箱地址", "收件人邮箱地址");
            message.Subject = "测试";
            message.Body = "用自己写的软件发的邮件！";
            message.BodyEncoding = System.Text.Encoding.UTF8;
            message.IsBodyHtml = true;

            try
            {
                client.Send(message);
                MessageBox.Show("Email successfully send.");
            }
            catch (Exception ex)
            {
                MessageBox.Show("Send Email Failed." + ex.ToString());
            }