Null Reference Exception on MVVM pattern

Posted by Mohit Deshpande on Stack Overflow See other posts from Stack Overflow or by Mohit Deshpande
Published on 2010-03-14T13:43:36Z Indexed on 2010/03/14 13:55 UTC
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System.NullReferenceException Object reference not set to an instance of an object. at Microsoft.Windows.Design.DocumentModel.Trees.MarkupDocumentTreeManager.<FindMarkupNodePath>d__0.MoveNext() at System.Linq.Enumerable.FirstOrDefault[TSource](IEnumerable1 source) at MS.Internal.Services.DocumentInformationServiceImpl.get_Root() at MS.Internal.Designer.VSDesigner.Load() at MS.Internal.Designer.VSIsolatedDesigner.VSIsolatedView.Load() at MS.Internal.Designer.VSIsolatedDesigner.VSIsolatedDesignerFactory.Load(IsolatedView view) at MS.Internal.Host.Isolation.IsolatedDesigner.BootstrapProxy.LoadDesigner(IsolatedDesignerFactory factory, IsolatedView view) at MS.Internal.Host.Isolation.IsolatedDesigner.BootstrapProxy.LoadDesigner(IsolatedDesignerFactory factory, IsolatedView view) at MS.Internal.Host.Isolation.IsolatedDesigner.Load() at MS.Internal.Designer.DesignerPane.LoadDesignerView()
I keep getting this exception and then intellisense stops working in a XAML text editor. Any ideas why?

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