Is a filter for the hpp header folder included in your project?
You can check by right-clicking on the Header Files folder to go to the properties, and it should have something like h; hpp; hxx; hm; inl; inc; xsd defined in the Filter property.
This can sometimes be a dodgy feature of Visual Studio that I have discovered since upgrading to Visual Studio 2010 that it takes too much time to use the goto definition or goto declaration to such an extent that I completely stop using it in favor of just looking for a project or solution and select it from the output window.
Ajg85
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