2014-01-24 15:05:04.2277 NLog.LoggerImpl.Write Error: Exception:  System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.NullReferenceException: Object reference not set to an instance of an object.
   at Doit.im.ViewModel.AdvancedFilterViewModel..ctor(Box box)
   at Doit.im.MainWindow.OnEditFilter(Object o, FilterEventArgs e)
   --- End of inner exception stack trace ---
   at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)
   at System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments)
   at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
   at System.Reflection.MethodBase.Invoke(Object obj, Object[] parameters)
   at GalaSoft.MvvmLight.Command.RelayCommand`1.Execute(Object parameter)
   at System.Windows.Controls.MenuItem.InvokeClickAfterRender(Object arg)
   at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   at MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(Object source, Delegate method, Object args, Int32 numArgs, Delegate catchHandler) Dispatcher.CatchException => App.OnDispatcherUnhandledException => LoggerImpl.Write
2014-01-24 15:05:04.2277 NLog.LoggerImpl.Write Error: Exception has been thrown by the target of an invocation.  Dispatcher.CatchException => App.OnDispatcherUnhandledException => LoggerImpl.Write