I created a Xamarin portable platforms app which contains four projects, Portable, Android, iOS and Windows Phone. When I make the Windows Phone project the start up project and then select menu > Project > Store, the store menu is disabled. St this point I am not able to reserve an app name or link my app to a registered app name. Menu item Associate app with the store is also disabled. Is there anyway of fixing this problem, I have no way of publishing my app.