System.InvalidOperationException: 'Dispatcher processing has been suspended, but messages are still being processed.'

Question

I created a blank WPF Application

<Window x:Class="WpfApp4.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApp4"
        mc:Ignorable="d"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <WebBrowser Name="WebBrowser1" ></WebBrowser>
    </Grid>
</Window>

When I Click Run, this Exception appears

System.InvalidOperationException: 'Dispatcher processing has been suspended, but messages are still being processed.'

If I remove the WebBrowser, then the App runs without Exception. It was giving this Exception, then a few moments ago, I could run similar code, not it is giving me this unexpected Exception, then now it insists with this Exception. How to solve it?

I think that this problem started after Visual Studio updated to Version 15.4.0 .

My Windows: Microsoft Windows [version 10.0.15063]

Stack Trace:

System.InvalidOperationException occurred
  HResult=0x80131509
  Message=Dispatcher processing has been suspended, but messages are still being processed.
  Source=<Cannot evaluate the exception source>
  StackTrace:
   at System.Windows.Threading.Dispatcher.WndProcHook(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o)
   at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
   at System.Windows.Threading.Dispatcher.LegacyInvokeImpl(DispatcherPriority priority, TimeSpan timeout, Delegate method, Object args, Int32 numArgs)
   at MS.Win32.HwndSubclass.SubclassWndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam)
   at MS.Win32.UnsafeNativeMethods.IOleObject.SetClientSite(IOleClientSite pClientSite)
   at System.Windows.Interop.ActiveXHost.TransitionFromLoadedToRunning()
   at System.Windows.Interop.ActiveXHost.TransitionUpTo(ActiveXState state)
   at System.Windows.Interop.ActiveXHost.BuildWindowCore(HandleRef hwndParent)
   at System.Windows.Interop.HwndHost.BuildWindow(HandleRef hwndParent)
   at System.Windows.Interop.HwndHost.BuildOrReparentWindow()
   at System.Windows.Interop.HwndHost.OnSourceChanged(Object sender, SourceChangedEventArgs e)
   at System.Windows.SourceChangedEventArgs.InvokeEventHandler(Delegate genericHandler, Object genericTarget)
   at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target)
   at System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs)
   at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
   at System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args)
   at System.Windows.UIElement.RaiseEvent(RoutedEventArgs e)
   at System.Windows.PresentationSource.UpdateSourceOfElement(DependencyObject doTarget, DependencyObject doAncestor, DependencyObject doOldParent)
   at System.Windows.PresentationSource.OnVisualAncestorChanged(DependencyObject uie, AncestorChangedEventArgs e)
   at System.Windows.UIElement.OnVisualAncestorChanged(Object sender, AncestorChangedEventArgs e)
   at System.Windows.Media.Visual.ProcessAncestorChangedNotificationRecursive(DependencyObject e, AncestorChangedEventArgs args)
   at System.Windows.Media.Visual.ProcessAncestorChangedNotificationRecursive(DependencyObject e, AncestorChangedEventArgs args)
   at System.Windows.Media.Visual.FireOnVisualParentChanged(DependencyObject oldParent)
   at System.Windows.Media.Visual.AddVisualChild(Visual child)
   at System.Windows.FrameworkElement.set_TemplateChild(UIElement value)
   at System.Windows.Controls.ContentPresenter.UseContentTemplate.BuildVisualTree(FrameworkElement container)
   at System.Windows.StyleHelper.ApplyTemplateContent(UncommonField`1 dataField, DependencyObject container, FrameworkElementFactory templateRoot, Int32 lastChildIndex, HybridDictionary childIndexFromChildID, FrameworkTemplate frameworkTemplate)
   at System.Windows.FrameworkTemplate.ApplyTemplateContent(UncommonField`1 templateDataField, FrameworkElement container)
   at System.Windows.FrameworkElement.ApplyTemplate()
   at System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   at System.Windows.UIElement.Measure(Size availableSize)
   at System.Windows.Documents.AdornerDecorator.MeasureOverride(Size constraint)
   at System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   at System.Windows.UIElement.Measure(Size availableSize)
   at System.Windows.Controls.Border.MeasureOverride(Size constraint)
   at System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   at System.Windows.UIElement.Measure(Size availableSize)
   at System.Windows.Window.MeasureOverrideHelper(Size constraint)
   at System.Windows.Window.MeasureOverride(Size availableSize)
   at System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   at System.Windows.UIElement.Measure(Size availableSize)
   at System.Windows.Interop.HwndSource.SetLayoutSize()
   at System.Windows.Interop.HwndSource.set_RootVisualInternal(Visual value)
   at System.Windows.Interop.HwndSource.set_RootVisual(Visual value)
   at System.Windows.Window.SetRootVisual()
   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.CreateSourceWindowDuringShow()
   at System.Windows.Window.SafeCreateWindowDuringShow()
   at System.Windows.Window.ShowHelper(Object booleanBox)
   at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
   at System.Windows.Threading.DispatcherOperation.InvokeImpl()
   at System.Windows.Threading.DispatcherOperation.InvokeInSecurityContext(Object state)
   at MS.Internal.CulturePreservingExecutionContext.CallbackWrapper(Object obj)
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at MS.Internal.CulturePreservingExecutionContext.Run(CulturePreservingExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Windows.Threading.DispatcherOperation.Invoke()
   at System.Windows.Threading.Dispatcher.ProcessQueue()
   at System.Windows.Threading.Dispatcher.WndProcHook(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o)
   at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
   at System.Windows.Threading.Dispatcher.LegacyInvokeImpl(DispatcherPriority priority, TimeSpan timeout, Delegate method, Object args, Int32 numArgs)
   at MS.Win32.HwndSubclass.SubclassWndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam)
   at MS.Win32.UnsafeNativeMethods.DispatchMessage(MSG& msg)
   at System.Windows.Threading.Dispatcher.PushFrameImpl(DispatcherFrame frame)
   at System.Windows.Threading.Dispatcher.PushFrame(DispatcherFrame frame)
   at System.Windows.Application.RunDispatcher(Object ignore)
   at System.Windows.Application.RunInternal(Window window)
   at System.Windows.Application.Run(Window window)
   at System.Windows.Application.Run()
   at WpfApp4.App.Main()

My Visual Studio 2017 Info:

Microsoft Visual Studio Community 2017 Version 15.4.0 VisualStudio.15.Release/15.4.0+27004.2002 Microsoft .NET Framework Version 4.7.02046

Installed Version: Community

Visual Basic 2017 00369-60000-00001-AA133 Microsoft Visual Basic 2017

Visual C# 2017 00369-60000-00001-AA133 Microsoft Visual C# 2017

Visual F# 4.1 00369-60000-00001-AA133 Microsoft Visual F# 4.1

Application Insights Tools for Visual Studio Package 8.9.00809.2 Application Insights Tools for Visual Studio

ASP.NET and Web Tools 2017 15.0.30925.0 ASP.NET and Web Tools 2017

ASP.NET Core Razor Language Services 1.0 Provides languages services for ASP.NET Core Razor.

ASP.NET Web Frameworks and Tools 2017 5.2.50921.0 For additional information, visit https://www.asp.net/

Azure App Service Tools v3.0.0 15.0.30915.0 Azure App Service Tools v3.0.0

Common Azure Tools 1.10 Provides common services for use by Azure Mobile Services and Microsoft Azure Tools.

JavaScript Language Service 2.0 JavaScript Language Service

JavaScript Project System 2.0 JavaScript Project System

JavaScript UWP Project System 2.0 JavaScript UWP Project System

Merq 1.1.17-rc (cba4571) Command Bus, Event Stream and Async Manager for Visual Studio extensions.

Microsoft Azure Tools 2.9 Microsoft Azure Tools for Microsoft Visual Studio 2017 - v2.9.50719.1

Microsoft Continuous Delivery Tools for Visual Studio 0.3 Simplifying the configuration of continuous build integration and continuous build delivery from within the Visual Studio IDE.

Microsoft JVM Debugger 1.0 Provides support for connecting the Visual Studio debugger to JDWP compatible Java Virtual Machines

Microsoft MI-Based Debugger 1.0 Provides support for connecting Visual Studio to MI compatible debuggers

Microsoft Visual Studio VC Package 1.0 Microsoft Visual Studio VC Package

Mono Debugging for Visual Studio 4.7.4-pre (c2d89eb) Support for debugging Mono processes with Visual Studio.

NuGet Package Manager 4.4.0 NuGet Package Manager in Visual Studio. For more information about NuGet, visit http://docs.nuget.org/.

SQL Server Data Tools 15.1.61707.200 Microsoft SQL Server Data Tools

TypeScript 2.3.5.0 TypeScript tools for Visual Studio

Visual Studio Code Debug Adapter Host Package 1.0 Interop layer for hosting Visual Studio Code debug adapters in Visual Studio

Visual Studio Tools for Universal Windows Apps 15.0.27004.2002 The Visual Studio Tools for Universal Windows apps allow you to build a single universal app experience that can reach every device running Windows 10: phone, tablet, PC, and more. It includes the Microsoft Windows 10 Software Development Kit.

VisualStudio.IoT 1.0 Package with IoT components for Visual Studio

VisualStudio.Mac 1.0 Mac Extension for Visual Studio

WebJobs Tools v1.0.0 15.0.30923.0 WebJobs Tools v1.0.0

Xamarin 4.7.10.22 (fe36bec) Visual Studio extension to enable development for Xamarin.iOS and Xamarin.Android.

Xamarin.Android SDK 8.0.0.33 (HEAD/7a6a056e8) Xamarin.Android Reference Assemblies and MSBuild support.

Xamarin.iOS and Xamarin.Mac SDK 11.2.0.8 (9a9f054) Xamarin.iOS and Xamarin.Mac Reference Assemblies and MSBuild support.

I reported this problem here https://developercommunity.visualstudio.com/content/problem/131554/dispatcher-processing-has-been-suspended-but-messa.html

I filled a bug track here https://connect.microsoft.com/VisualStudio/feedback/details/3142780

Any code-behind or references to other DLLs? Have you try a new solution? If still, it must be something wrong with the Visual Studio, just reinstall it to have a try. — Iron, Oct 14 '17 at 18:16
I just tried a new solution. I was having this issue on a old Project here, until I discovered it was related to WebBrowser, then I created a new Project, put the WebBrowser, hit Play, and the Exception appears from nowhere in my code. There is no my code behind. Just the control and the XAML. — Tony, Oct 15 '17 at 00:20
Please post the stack trace, this can be interesting. Disable the 'just my code' setting and enable the .NET source debugging for a better stack trace. — dymanoid, Oct 16 '17 at 14:35
In the stack trace, there are a `Border`, an `AdornerDecorator`, and a template. Are you sure you're not using any additional styles, templates etc? — dymanoid, Oct 17 '17 at 11:50
Yes, I Just created that WPF Project, put the WebBrowser, and 1% of the time, the Project runs, then it starts to give that exception. Now I opened the Project Run the Window with the Browser appeared. I stopped. Run again, then the Exception appears. — Tony, Oct 17 '17 at 12:13
I reported this problem here https://developercommunity.visualstudio.com/content/problem/131554/dispatcher-processing-has-been-suspended-but-messa.html — Tony, Oct 18 '17 at 15:12
I filled a bug track here https://connect.microsoft.com/VisualStudio/feedback/details/3142780 — Tony, Oct 20 '17 at 00:15
I made a Time Travel Debug, and uploaded the files WpfApp401.idx WpfApp401.run zipped : https://drive.google.com/open?id=0B5d9oJc6UeFKNGRReWJhWWx5UHM — Tony, Oct 25 '17 at 20:08

score 4 · Answer 1 · answered Oct 25 '17 at 19:59

4

The problem went away after I uninstalled this Internet Banking Plugin:

answered Oct 25 '17 at 19:59

Tony

16,527
15
80
134

2

You saved my day. Ou melhor... salvou meu dia, obrigado! – Kevin Kouketsu Jan 28 '20 at 16:25
3

`Internet Banking Plugin`. Those are some pretty scary words... – highboi Feb 09 '21 at 16:31
How in the world does this have four upvotes. Anyone know what the actual issue was? – Simon_Weaver Jun 17 '23 at 00:38

score 1 · Answer 2 · answered Jul 21 '18 at 15:42

1

Just navigate to url on start, solved to me.

public MainWindow()
{
    InitializeComponent();
    browser.Navigate("about:blank");
}

answered Jul 21 '18 at 15:42

Gilberto Alexandre

2,227
1
18
20

score 0 · Answer 3 · answered Jun 17 '23 at 00:40

0

I had this issue, appearing recently on a WPF app that's been around for years (more details in my question).

In short, enabling Prefer 32 bit in the Release configuration fixed it for us. And made it faster too.

Absolutely no clue why yet!

answered Jun 17 '23 at 00:40

Simon_Weaver

140,023
84
646
689

System.InvalidOperationException: 'Dispatcher processing has been suspended, but messages are still being processed.'

3 Answers3