Failed to connect to third party, using smtp client?

Question

Hi Team

 

I have this issue, each time i am registering the new user, its connection failure to third party. I am using smtp client mail and this domain is gmail. The question why am i getting this often and its not even send a confirming email to the user. It does writes this query to the database colum. What could an issue?

[HttpPost]
  [AllowAnonymous]
  [ValidateAntiForgeryToken]
  public async Task<ActionResult> Register(RegisterViewModel model)
  {
      if (ModelState.IsValid)
      {
          var user = new ApplicationUser() { UserName = model.UserName };
          user.Email = model.Email;
          user.ConfirmedEmail = false;
          var result = await UserManager.CreateAsync(user, model.Password);
          if (result.Succeeded)
          {
              System.Net.Mail.MailMessage m = new System.Net.Mail.MailMessage(
                  new System.Net.Mail.MailAddress("[email protected]", "Web Registration"),
                  new System.Net.Mail.MailAddress(user.Email));
              m.Subject = "Email confirmation";
              m.Body = string.Format("Dear {0}<BR/>Thank you for your registration, please click on the below link to complete your registration: <a href=\"{1}\" title=\"User Email Confirm\">{1}</a>", user.UserName, Url.Action("ConfirmEmail", "Account", new { Token = user.Id, Email = user.Email }, Request.Url.Scheme));
              m.IsBodyHtml = true;
              System.Net.Mail.SmtpClient smtp = new System.Net.Mail.SmtpClient("smtp.gmail.com");
              smtp.Credentials = new System.Net.NetworkCredential("[email protected]", "password");
              smtp.EnableSsl = true;
              smtp.Send(m);
              return RedirectToAction("Confirm", "Account", new { Email = user.Email });
          }
          else
          {
              AddErrors(result);
          }
      }

      // If we got this far, something failed, redisplay form
      return View(model);
  }