Created Unassigned: Property Grid crashes VS Designer [20639]

As soon as I add a PropertyGrid to my window, the VS designer windows does not show my layout but the the following exception:

NullReferenceException: Object reference not set to an instance of an object.
Stack Trace:
at Microsoft.VisualStudio.ExpressionHost.Platform.DTEReferenceResolver.GetReferences(IHostProject project, Object& connectionPointSource)
at Microsoft.VisualStudio.ExpressionHost.Platform.PlatformUtilities.GetReferenceResolver(IServiceProvider services, HostProject project)
at Microsoft.VisualStudio.ExpressionHost.HostServices.HostProject.Microsoft.Expression.DesignHost.IHostProject.get_References()
at Microsoft.Expression.DesignHost.Isolation.Remoting.RemoteHostProject.<Microsoft.Expression.DesignHost.Isolation.Remoting.IRemoteHostProject.get_References>b__6b()
at Microsoft.Expression.DesignHost.Isolation.Remoting.ThreadMarshaler.<>c__DisplayClass16`1.<MarshalIn>b__15()
at Microsoft.Expression.DesignHost.Isolation.Remoting.STAMarshaler.Call.InvokeWorker()
InnerException: None

I'm using VS2012