title: What is the exception that makes to throw a Task.ThrowIfExceptional?
body: <p>I have a windows forms app developed with C# and .NET Framework 4.0 running Task.</p>
  
  <p>I'm sorry to ask this question but I don't know where an exception occur. This is the stack trace:</p>
  
  <pre><code>One or more errors occurred.
     at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
     at System.Threading.Tasks.Task.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken)
     at MyCompany.Dispositivos.Plugins.TICAnKorr.DeviceTICAnKorr.StopLive()
     at MyCompany.Dispositivos.Plugins.TICAnKorr.VisorTICAnKorrMini.StopRemote()
     at MyCompany.Dispositivos.InterfazDispositivos.ICBaseVisor.DesasociarDispositivo()
     at MyCompany.Dispositivos.InterfazDispositivos.ControlMosaico.DesasociarTodosLosPaneles()
     at MyCompany.Dispositivos.InterfazDispositivos.ControlMosaico.CrearControlSeleccionado(DeviceBase device)
     at MyCompany.Dispositivos.InterfazDispositivos.ControlMosaico.icPanelViewer_MouseDown(Object sender, MouseEventArgs e)
     at System.Windows.Forms.Control.OnMouseDown(MouseEventArgs e)
     at System.Windows.Forms.UserControl.OnMouseDown(MouseEventArgs e)
     at MyCompany.Dispositivos.InterfazDispositivos.VisorDeMosaico.mousedown(Object sender, MouseEventArgs e)
     at System.Windows.Forms.Control.OnMouseDown(MouseEventArgs e)
     at System.Windows.Forms.UserControl.OnMouseDown(MouseEventArgs e)
     at MyCompany.BasicInterface.Controles_Basicos.ICLabel.lblText_MouseDown(Object sender, MouseEventArgs e)
     at System.Windows.Forms.Control.OnMouseDown(MouseEventArgs e)
     at System.Windows.Forms.Control.WmMouseDown(Message&amp; m, MouseButtons button, Int32 clicks)
     at System.Windows.Forms.Control.WndProc(Message&amp; m)
     at System.Windows.Forms.Label.WndProc(Message&amp; m)
     at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message&amp; m)
     at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message&amp; m)
     at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
  Object reference not set to an instance of an object.
     at MyCompany.Dispositivos.Plugins.TICAnKorr.VisorTICAnKorrMini.MensajeEstado()
     at MyCompany.Dispositivos.Plugins.TICAnKorr.VisorTICAnKorrMini.m_DispositivoAsociado_NewResult(Object sender)
     at MyCompany.Dispositivos.ConexionesDispositivos.NewResultsEventHandler.Invoke(Object sender)
     at MyCompany.Dispositivos.ConexionesDispositivos.DeviceBase.OnNewResult()
     at MyCompany.Dispositivos.Plugins.TICAnKorr.DeviceTICAnKorr.HiloCaptura()
     at MyCompany.Dispositivos.ConexionesDispositivos.DeviceBase.&lt;StartLive&gt;b__9()
     at System.Threading.Tasks.Task.InnerInvoke()
     at System.Threading.Tasks.Task.Execute()
  </code></pre>
  
  <p>I think the exception thrown is this:</p>
  
  <pre><code>Object reference not set to an instance of an object.
         at MyCompany.Dispositivos.Plugins.TICAnKorr.VisorTICAnKorrMini.MensajeEstado()
  </code></pre>
  
  <p>What is the real exception?</p>
  
  <p>If this is not the right place to ask this question, please tell me and I delete it.</p>
  
  <p>I'm not asking about what is the meaning of <code>Object reference not set to an instance of an object.</code>, I know it, I'm asking if this the exception that makes the task to throw a <code>System.Threading.Tasks.Task.ThrowIfExceptional</code>. </p>