Blend 5 Preview designer crashes after VS rebuild

Question

I am working on a big silverlight project, and have problems editing it in Blend; Initially, Blend starts properly, designer shows the controls, etc.

However, unexpectedly, after parallel work in VisualStudio and at least one rebuild, I get this exception

XamlParseException: [Line: 0 Position 0]

StackTrace
at MS.Internal.XcpImports.CheckHResult(UInt32 hr)
at MS.Internal.XcpImports.FrameworkElement_MeasureOverride(FrameworkElement element, Size     availableSize)
at System.Windows.FrameworkElement.MeasureOverride(Size availableSize)
at System.Windows.FrameworkElement.MeasureOverride(IntPtr nativeTarget, Single inWidth, Single   inHeight, Single& outWidth, Single& outHeight)

Any idea? Thanks

Edit: Is it maybe because of TFS?