当我在设计师中加载XAML文件时，我会收到以下异常，然后我必须从进程管理器中终止VS 2012。有什么解决方法吗？
Microsoft.Expression.DesignHost.Isolation.Remoting.RemoteException
Object reference not set to an instance of an object.
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)
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.MarshalOut(Action action, Int32 targetApartmentId, WaitHandle aborted, CallSynchronizationMode syncMode, WaitHandle timeoutSignal)
at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.MarshalOut[TValue](RemoteHandle`1 targetObject, Action action, CallSynchronizationMode syncMode)
at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.MarshalOut[TResult,TValue](RemoteHandle`1 targetObject, Func`2 func, CallSynchronizationMode syncMode)
at Microsoft.Expression.DesignHost.Isolation.Remoting.LocalHostTextBufferSynchronizer.get_IsReadOnly()
at Microsoft.Expression.DesignHost.DesignerTextBufferSynchronizer.get_IsReadOnly()
at Microsoft.Expression.DesignHost.DesignerTextBuffer.get_IsReadOnly()
at Microsoft.Expression.DesignSurface.Documents.TextBuffer.get_IsReadOnly()
at Microsoft.Expression.DesignSurface.Documents.SceneDocument.get_IsReadOnly()
at Microsoft.Expression.DesignSurface.Documents.SceneDocument.get_IsUndoTargetReadOnly()
at Microsoft.Expression.DesignSurface.Selection.SelectionSet`2.SetSelectionWithUndo(String description, ListOfT newSelection, T newPrimarySelection)
at Microsoft.Expression.DesignSurface.Selection.SceneNodeSelectionSet.SetSelectionWithUndo(String description, SceneNodeOrderedCollection newSelection, SceneNode newPrimarySelection)
at Microsoft.Expression.DesignSurface.Selection.SelectionSet`2.ExtendSelection(T selectionToExtend)
at Microsoft.Expression.DesignSurface.ViewModel.SceneViewModel.SelectNodes(ICollection`1 nodes)
at Microsoft.Expression.DesignSurface.View.SceneView.SelectionSynchronizer.OnCaretPositionChangedTimeoutTimerTick(TextEditorContext textEditor)
at Microsoft.Expression.DesignSurface.View.SceneView.SelectionSynchronizer.SynchronizeSceneToMarkup(TextEditorContext textEditor)
at Microsoft.Expression.DesignSurface.View.SceneView.TextEditor_CaretPositionChanged(Object sender, EventArgs e)
at Microsoft.Expression.DesignSurface.TextEditorContext.CaretPositionChangedPipe(Object sender, EventArgs args)
at Microsoft.Expression.DesignHost.Isolation.Remoting.LocalEvent`2.<>c__DisplayClass12.<Invoke>b__10()
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.Call.InvokeWorker()
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.Call.Invoke(Boolean waitingInExternalCall)
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.InvokeCall(Call call)
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.ProcessQueue(CallQueue queue)
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.ProcessInboundQueue(Int32 identity)
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.ProcessMessage(Int32 msg, IntPtr wParam, Boolean elevatedQuery, Boolean& handled)
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.OnWindowMessage(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
at Microsoft.Expression.DesignHost.Isolation.Remoting.MessageOnlyHwndWrapper.WndProc(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.Threading.Dispatcher.Run()
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 Microsoft.Expression.DesignHost.Isolation.IsolationProcess.RunApplication()
at Microsoft.Expression.DesignHost.Isolation.IsolationProcess.<>c__DisplayClass2.<Main>b__0()
at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
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 System.Threading.ThreadHelper.ThreadStart()
Microsoft.Expression.DesignHost.Isolation.Remoting.RemoteException
Object reference not set to an instance of an object.
Server stack trace:
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.WaitForCompletion(NestedCallContext nestedCallContext, BlockingCall call, WaitHandle timeoutSignal)
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.MarshalIn(Action action, Int32 targetApartmentId)
at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.MarshalIn(IRemoteObject targetObject, Action action)
at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.MarshalIn[TResult](IRemoteObject targetObject, Func`1 func)
at Microsoft.Expression.DesignHost.Isolation.Remoting.RemoteHostTextBufferSynchronizer.get_IsReadOnly()
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.IRemoteHostTextBufferSynchronizer.get_IsReadOnly()
at Microsoft.Expression.DesignHost.Isolation.Remoting.LocalHostTextBufferSynchronizer.<get_IsReadOnly>b__8(IRemoteHostTextBufferSynchronizer hs)
at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.<>c__DisplayClass4`2.<MarshalOut>b__3()
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.Call.InvokeWorker()
Microsoft.Expression.DesignHost.Isolation.Remoting.RemoteException
Object reference not set to an instance of an object.
at Microsoft.Expression.DesignHost.Isolation.Remoting.RemoteHostTextBufferSynchronizer.<get_IsReadOnly>b__7()
at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.<>c__DisplayClass16`1.<MarshalIn>b__15()
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.Call.InvokeWorker()