error, send gmail with smtp

public int SendUserMail(string fromad, string toad, string body, string header, string subjectcontent)
        {
            int result = 0;
            MailMessage usermail = Mailbodplain(fromad, toad, body, header, subjectcontent);
            SmtpClient client = new SmtpClient();
            //Add the Creddentials- use your own email id and password
            client.Credentials = new System.Net.NetworkCredential("mailFrom@gmail.com ", "PWD");

            client.Host = "smtp.gmail.com";
            client.Port = 587;
            client.EnableSsl = true;
            try
            {
                client.Send(usermail);
                result = 1;
            }
            catch (Exception ex)
            {
                result = 0;
            } // end try 

            return result;

        }

public MailMessage Mailbodplain(string fromad, string toad, string body, string header, string subjectcontent)
       {
           System.Net.Mail.MailMessage mail = new System.Net.Mail.MailMessage();
           try
           {
               string from = fromad;
               string to = toad;
               mail.To.Add(to);
               mail.From = new MailAddress(from, header, System.Text.Encoding.UTF8);
               mail.Subject = subjectcontent;
               mail.SubjectEncoding = System.Text.Encoding.UTF8;
               mail.Body = body;
               //Attachment att = new Attachment("G:\\code.txt");
               //newmsg.Attachments.Add(att);
               mail.BodyEncoding = System.Text.Encoding.UTF8;
               mail.IsBodyHtml = true;
               mail.Priority = MailPriority.High;
           }
           catch (Exception ex)
           {
               throw;
           }
           return mail;
       }