[Windows Phone 8 General] mapleleafs89:
Thanks!

Anyone know why when you create a new Windows Store app targeting WP 8.1 in Visual Studio Pro 2013 the designer for XAML pages won't load?

I get

System.InvalidCastException
Specified cast is not valid.
at MS.Internal.XcpImports.CheckHResult(UInt32 hr)
at MS.Internal.XcpImports.DependencyProperty_GetDefaultValue(DependencyProperty dp, DependencyObject propertyOwner, UInt32 propertyOwnerTypeId)
at System.Windows.CoreDependencyProperty.GetMetadata(UInt32 propertyOwnerTypeId)
at System.Windows.CoreDependencyProperty.GetMetadataCore(Type forType)
at Microsoft.Expression.SilverlightPlatform.SilverlightDependencyPropertyImplementation.GetDefaultValue(IType targetType)
at Microsoft.Expression.DesignModel.Metadata.DependencyPropertyReferenceStep.GetDefaultValue(IType targetType)
at Microsoft.Expression.SilverlightPlatform.SilverlightDesignTimeProperties.ResolveImplementation(IPlatformMetadata platformMetadata, DesignTimePropertyId neutralProperty, IType declaringType, PropertyChangedCallback callback)
at Microsoft.Expression.SilverlightPlatform.SilverlightDesignTimeProperties.RegisterProperty(IPropertyId neutralPropertyKey, IType declaringType, PropertyChangedCallback callback)
at Microsoft.Expression.SilverlightPlatform.SilverlightMiscDesignTimeProperties.Initialize(SilverlightDesignTimeProperties designTimeProperties)
at Microsoft.Expression.SilverlightPlatform.SilverlightDesignTimeProperties..ctor(IPlatformTypes platformMetadata)
at Microsoft.Expression.SilverlightPlatform.SilverlightPlatformMetadata.Initialize()
at Microsoft.Expression.SilverlightPlatform.SilverlightPlatform.Initialize()
at Microsoft.Expression.Platform.PlatformCreatorBase.CreatePlatform(IPlatformReferenceAssemblyResolver referenceAssemblyResolver)
at Microsoft.Expression.DesignSurface.Project.ProjectContextManager.GetProjectContext(IHostProject project, IPlatform platform, Boolean create)
at Microsoft.Expression.DesignSurface.Project.ProjectContextManager.GetSourceItemContext(IHostSourceItem sourceItem)
at Microsoft.Expression.DesignSurface.DesignerService.CreateDesigner(IHostSourceItem item, IHostTextEditor editor, CancellationToken cancelToken)
at Microsoft.Expression.DesignHost.Isolation.Remoting.RemoteDesignerService.<>c__DisplayClass13.<Microsoft.Expression.DesignHost.Isolation.Remoting.IRemoteDesignerService.CreateDesigner>b__12(CancellationToken cancelToken)
at Microsoft.Expression.DesignHost.Isolation.Remoting.RemoteDesignerService.<>c__DisplayClass3`1.<MarshalInWithCancellation>b__2()
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.Call.InvokeWorker()

System.InvalidCastException
Specified cast is not valid.

Server stack trace:
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.WaitForCompletion(NestedCallContext nestedCallContext, BlockingCall call, WaitHandle timeoutSignal)
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.MarshalInSynchronous(Action action, Int32 targetApartmentId, CancellationToken cancelToken, CallModality callModality, String methodName, String filePath, Int32 lineNumber)
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.MarshalIn(Action action, Int32 targetApartmentId, CancellationToken cancelToken, CallSynchronizationMode syncMode, CallModality callModality, String methodName, String filePath, Int32 lineNumber)
at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.MarshalIn(IRemoteObject targetObject, Action action, CancellationToken cancelToken, CallSynchronizationMode syncMode, CallModality callModality, ApartmentState apartmentState, String memberName, String filePath, Int32 lineNumber)
at Microsoft.Expression.DesignHost.Isolation.Remoting.RemoteDesignerService.MarshalInWithCancellation[TResult](IRemoteCancellationToken remoteToken, Func`2 func, ApartmentState apartmentState)
at Microsoft.Expression.DesignHost.Isolation.Remoting.RemoteDesignerService.Microsoft.Expression.DesignHost.Isolation.Remoting.IRemoteDesignerService.CreateDesigner(IRemoteHostProject remoteProject, IRemoteHostSourceItem remoteItem, IRemoteHostTextEditor remoteEditor, IRemoteCancellationToken remoteToken)
at System.Runtime.Remoting.Messaging.StackBuilderSink._PrivateProcessMessage(IntPtr md, Object[] args, Object server, Object[]& outArgs)
at System.Runtime.Remoting.Messaging.StackBuilderSink.SyncProcessMessage(IMessage msg)

Exception rethrown at [0]:
at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg)
at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type)
at Microsoft.Expression.DesignHost.Isolation.Remoting.IRemoteDesignerService.CreateDesigner(IRemoteHostProject remoteProject, IRemoteHostSourceItem remoteItem, IRemoteHostTextEditor remoteEditor, IRemoteCancellationToken cancelToken)
at Microsoft.Expression.DesignHost.Isolation.Remoting.LocalDesignerService.CreateDesignerImpl(IRemoteDesignerService ds, IHostSourceItem item, IHostTextEditor editor, RemoteCancellationToken remoteCancelToken)
at Microsoft.Expression.DesignHost.Isolation.Remoting.LocalDesignerService.<>c__DisplayClass19.<Microsoft.Expression.DesignHost.IDesignerService.CreateDesigner>b__18(IRemoteDesignerService ds, RemoteCancellationToken remoteToken)
at Microsoft.Expression.DesignHost.Isolation.Remoting.LocalDesignerService.<>c__DisplayClass5`1.<MarshalOutWithCancellation>b__4(IRemoteDesignerService ds)
at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.<>c__DisplayClass1`1.<MarshalOut>b__0()
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.Call.InvokeWorker()

System.InvalidCastException
Specified cast is not valid.
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.WaitForCompletion(NestedCallContext nestedCallContext, BlockingCall call, WaitHandle timeoutSignal)
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.MarshalOutSynchronous(Action action, Int32 targetApartmentId, WaitHandle aborted, WaitHandle timeoutSignal, CancellationToken cancelToken, String methodName, String filePath, Int32 lineNumber)
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.MarshalOut(Action action, Int32 targetApartmentId, WaitHandle aborted, CancellationToken cancelToken, CallSynchronizationMode syncMode, WaitHandle timeoutSignal, String methodName, String filePath, Int32 lineNumber)
at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.MarshalOut[TValue](RemoteHandle`1 targetObject, Action action, CancellationToken cancelToken, CallSynchronizationMode syncMode, ApartmentState apartmentState, String methodName, String filePath, Int32 lineNumber)
at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.MarshalOut[TValue](RemoteHandle`1 targetObject, Action`1 action, CancellationToken cancelToken, CallSynchronizationMode syncMode, ApartmentState apartmentState, String methodName, String filePath, Int32 lineNumber)
at Microsoft.Expression.DesignHost.Isolation.Remoting.LocalDesignerService.MarshalOutWithCancellation[TResult](CancellationToken cancelToken, Func`3 func, ApartmentState apartmentState)
at Microsoft.Expression.DesignHost.Isolation.Remoting.LocalDesignerService.Microsoft.Expression.DesignHost.IDesignerService.CreateDesigner(IHostSourceItem item, IHostTextEditor editor, CancellationToken cancelToken)
at Microsoft.Expression.DesignHost.IsolatedDesignerService.IsolatedDesignerView.CreateDesignerViewInfo(CancellationToken cancelToken)