public async Task SendFallMail(string path){
            try
            {
                mail.Subject = subjectFall;
                mail.Body = "Fall down!";

                using (MailMessage ms = mail) {
                    ms.Attachments.Add(new Attachment(path));
                    using (SmtpClient sc = SmtpServer)
                    {
                        Task t = Task.Factory.StartNew(() =>
                        { 
                            sc.Send(ms); 
                        });
                        await t;
                    }
                }
                File.Delete(path);
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.ToString());
            }