System.InvalidOperationException: Cannot use a DependencyObject that belongs to a different thread than its parent Freezable <p>I have this problem... but can't figure out where is coming from. Do you know of a way to debug this? This happens in a WPF application that has several windows each running in different dispatchers.</p> <pre><code>System.InvalidOperationException: Cannot use a DependencyObject that belongs to a different thread than its parent Freezable. at System.Windows.Freezable.EnsureConsistentDispatchers(DependencyObject owner, DependencyObject child) at System.Windows.Freezable.OnFreezablePropertyChanged(DependencyObject oldValue, DependencyObject newValue, DependencyProperty property) at System.Windows.Media.RenderData.PropagateChangedHandler(EventHandler handler, Boolean adding) at System.Windows.UIElement.RenderClose(IDrawingContent newContent) at System.Windows.Media.RenderDataDrawingContext.DisposeCore() at System.Windows.Media.DrawingContext.System.IDisposable.Dispose() at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.StackPanel.ArrangeOverride(Size arrangeSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Grid.ArrangeOverride(Size arrangeSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.DockPanel.ArrangeOverride(Size arrangeSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Control.ArrangeOverride(Size arrangeBounds) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Grid.ArrangeOverride(Size arrangeSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Grid.ArrangeOverride(Size arrangeSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Control.ArrangeOverride(Size arrangeBounds) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Control.ArrangeOverride(Size arrangeBounds) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Grid.ArrangeOverride(Size arrangeSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Border.ArrangeOverride(Size finalSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Grid.ArrangeOverride(Size arrangeSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Control.ArrangeOverride(Size arrangeBounds) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Grid.ArrangeOverride(Size arrangeSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Grid.ArrangeOverride(Size arrangeSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Grid.ArrangeOverride(Size arrangeSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at MS.Internal.Helper.ArrangeElementWithSingleChild(UIElement element, Size arrangeSize) at System.Windows.Controls.ContentPresenter.ArrangeOverride(Size arrangeSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Grid.ArrangeOverride(Size arrangeSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Control.ArrangeOverride(Size arrangeBounds) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.DockPanel.ArrangeOverride(Size arrangeSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Border.ArrangeOverride(Size finalSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at MS.Internal.Helper.ArrangeElementWithSingleChild(UIElement element, Size arrangeSize) at System.Windows.Controls.ContentPresenter.ArrangeOverride(Size arrangeSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Grid.ArrangeOverride(Size arrangeSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Border.ArrangeOverride(Size finalSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Grid.ArrangeOverride(Size arrangeSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Border.ArrangeOverride(Size finalSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Controls.Border.ArrangeOverride(Size finalSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Documents.AdornerDecorator.ArrangeOverride(Size finalSize) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Window.ArrangeOverride(Size arrangeBounds) at Syncfusion.Windows.Shared.ChromelessWindow.ArrangeOverride(Size arrangeBounds) at System.Windows.FrameworkElement.ArrangeCore(Rect finalRect) at System.Windows.UIElement.Arrange(Rect finalRect) at System.Windows.Interop.HwndSource.SetLayoutSize() at System.Windows.Interop.HwndSource.set_RootVisualInternal(Visual value) at System.Windows.Window.SetRootVisualAndUpdateSTC() at System.Windows.Window.SetupInitialState(Double requestedTop, Double requestedLeft, Double requestedWidth, Double requestedHeight) at System.Windows.Window.CreateSourceWindow(Boolean duringShow) at System.Windows.Window.ShowHelper(Object booleanBox) at Djali.Services.WindowInfo.PreloadWindow() in c:\src-tfs\Development\Djali\Djali\Services\GuiThreadsService.cs:line 612 at Djali.Services.GuiThreadsService.&lt;&gt;c__DisplayClass20.&lt;InitializeRuntime&gt;b__11() in c:\src-tfs\Development\Djali\Djali\Services\GuiThreadsService.cs:line 293 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) </code></pre>