Microsoft seems to have given up on guidance for how to write desktop apps, Windows 8 had that Metro thing that got rejected by the world. I guess you could use Win32, WinForms, WPF or something else. The incoherence is second only to the Linux world, I remember how developers were crazy about theming in Win32 in the ‘95 age so something like Back Orifice or the app for your scanner looks atrocious. WPF added really great support for theming but at the point everybody was burned out in theming so it hardly ever got used.