title: Error: An asynchronous module or handler completed while an asynchronous operation was still pending
body: <p>I have a Controller Action method to Save user Details like below.</p>
  
  <pre><code>public async Task&lt;ActionResult&gt; SaveUser(ViewModel.VM_CreateUser user)
  {
      var result = await _user.Save(userDetails);
      return Json(new { Success = String.IsNullOrEmpty(result) });
  }
  </code></pre>
  
  <p>So far there is no issue in above 4 lines function.</p>
  
  <pre><code>public async Task&lt;ActionResult&gt; SaveUser(ViewModel.VM_CreateUser user)
  {
      var result = await _user.Save(userDetails);
      new MailController().CreateUser(user.userDetails); //&lt;==This is problem line of code.
  }
  </code></pre>
  
  <p>and Below is my Mail Controller.</p>
  
  <pre><code>public class MailController : MailerBase
  {
      public void CreateUser(ViewModel.VM_User user)
      {
          To.Add(user.EmailAddress);
          From = System.Configuration.ConfigurationManager.AppSettings["emailSender"];
          Subject = "Hi";
          Email("CreateUser", user).DeliverAsync();
      }
  }
  </code></pre>
  
  <p>in the above code, I am facing problem when I execute the Email Sending code. I get below error message.</p>
  
  <blockquote>
    <p>An asynchronous module or handler completed while an asynchronous
    operation was still pending</p>
  </blockquote>
  
  <p>Please suggest the corrective action !!</p>