When adding an ActiveX control onto a Visual Studio 2008 or 2010 Form, you get an error message stating Failed to create component ‘AxHost’, followed by some other text. This is caused any existing AxInterop.????.dll and Interop.?????.dll file that may already existing in the Project\obj\Debug folder. This is not to be confused with the Project\bin\Debug directory.
To correct, remove any Project level reference, then delete the 2 dll files. Then you can add the ActiveX control to the Form without any error.