COM exception while initialising managed Metro component in Windows 8
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I'm working on a complex Metro C# / XAML library and I'm seeing occasional failures in InitializeComponent that I'm finding it impossible to debug:

System.Exception: Exception from HRESULT: 0x880008AF
   at Windows.UI.Xaml.FrameworkElement.MeasureOverride(Size availableSize)

The problem is that this is being caught in the unhandled exception catch all in the App class and there is no stack trace and no further exception information beyond the text quoted above.

I've switched off the managed unhandled exception catch-all and set windbg as the default debugger for crashed processes, and then I can see the unmanaged call stack and exactly where this is failing, but I don't have any experience with windbg and so I haven't been able to dig up the details of exactly why the failure is happening.

I've also set "break on all exceptions" in Visual Studio 2012, but I'm not seeing any first chance exceptions in the managed code.

Has anyone come across problems like this with managed Metro apps in Win 8 and been able to get beyond the generic error message?

Thanks