Question

Steps to reproduce:

1. Create new WPF project
2. Set AllowsTransparency="True" to the Window
3. Run
4. Look at the system logs

In my case on both windows 7 PCs I have in logs:

Application: WpfApplication1.exe
Framework Version: v4.0.30319
Description: The process was terminated due to an unhandled exception.
Exception Info: System.InvalidOperationException
Stack:
   at System.Windows.Window.VerifyConsistencyWithAllowsTransparency(System.Windows.WindowStyle)
   at System.Windows.Window.CoerceVisibility(System.Windows.DependencyObject, System.Object)
   at System.Windows.DependencyObject.ProcessCoerceValue(System.Windows.DependencyProperty, System.Windows.PropertyMetadata, System.Windows.EntryIndex ByRef, Int32 ByRef, System.Windows.EffectiveValueEntry ByRef, System.Windows.EffectiveValueEntry ByRef, System.Object ByRef, System.Object, System.Object, System.Windows.CoerceValueCallback, Boolean, Boolean, Boolean)
   at System.Windows.DependencyObject.UpdateEffectiveValue(System.Windows.EntryIndex, System.Windows.DependencyProperty, System.Windows.PropertyMetadata, System.Windows.EffectiveValueEntry, System.Windows.EffectiveValueEntry ByRef, Boolean, Boolean, System.Windows.OperationType)
   at System.Windows.DependencyObject.SetValueCommon(System.Windows.DependencyProperty, System.Object, System.Windows.PropertyMetadata, Boolean, Boolean, System.Windows.OperationType, Boolean)
   at System.Windows.DependencyObject.SetValue(System.Windows.DependencyProperty, System.Object)
   at System.Windows.UIElement.set_Visibility(System.Windows.Visibility)
   at System.Windows.Application.ConfigAppWindowAndRootElement(System.Object, System.Uri)
   at System.Windows.Application.DoStartup()
   at System.Windows.Application.<.ctor>b__1(System.Object)
   at System.Windows.Threading.ExceptionWrapper.InternalRealCall(System.Delegate, System.Object, Int32)
   at MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(System.Object, System.Delegate, System.Object, Int32, System.Delegate)
   at System.Windows.Threading.DispatcherOperation.InvokeImpl()
   at System.Windows.Threading.DispatcherOperation.InvokeInSecurityContext(System.Object)
   at System.Threading.ExecutionContext.runTryCode(System.Object)
   at System.Runtime.CompilerServices.RuntimeHelpers.ExecuteCodeWithGuaranteedCleanup(TryCode, CleanupCode, System.Object)
   at System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object)
   at System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean)
   at System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object)
   at System.Windows.Threading.DispatcherOperation.Invoke()
   at System.Windows.Threading.Dispatcher.ProcessQueue()
   at System.Windows.Threading.Dispatcher.WndProcHook(IntPtr, Int32, IntPtr, IntPtr, Boolean ByRef)
   at MS.Win32.HwndWrapper.WndProc(IntPtr, Int32, IntPtr, IntPtr, Boolean ByRef)
   at MS.Win32.HwndSubclass.DispatcherCallbackOperation(System.Object)
   at System.Windows.Threading.ExceptionWrapper.InternalRealCall(System.Delegate, System.Object, Int32)
   at MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(System.Object, System.Delegate, System.Object, Int32, System.Delegate)
   at System.Windows.Threading.Dispatcher.InvokeImpl(System.Windows.Threading.DispatcherPriority, System.TimeSpan, System.Delegate, System.Object, Int32)
   at MS.Win32.HwndSubclass.SubclassWndProc(IntPtr, Int32, IntPtr, IntPtr)
   at MS.Win32.UnsafeNativeMethods.DispatchMessage(System.Windows.Interop.MSG ByRef)
   at System.Windows.Threading.Dispatcher.PushFrameImpl(System.Windows.Threading.DispatcherFrame)
   at System.Windows.Threading.Dispatcher.PushFrame(System.Windows.Threading.DispatcherFrame)
   at System.Windows.Threading.Dispatcher.Run()
   at System.Windows.Application.RunDispatcher(System.Object)
   at System.Windows.Application.RunInternal(System.Windows.Window)
   at System.Windows.Application.Run(System.Windows.Window)
   at System.Windows.Application.Run()
   at WpfApplication1.App.Main()

Can anyone confirm it?

Software I use: VS 2010 Express (SP1), Windows 7 home premium.

Answer 1

just the change the

WindowStyle=”None”