Xamarin.Android: error when calling Azure mobile services

In a mobile application I’m building with  Xamarin Android I connect to an Azure Mobile Services backend. Xamarin made this easy by providing an Azure Mobile Services component.

	[Activity (Label = "RunningAssistant", MainLauncher = true)]
	public class MainActivity : Activity
	{
	int count = 1;
	public static MobileServiceClient MobileService = new MobileServiceClient(
	"https://mymobileservice.azure-mobile.net/",
	"SharedKey"
	);
	protected override void OnCreate (Bundle bundle)
	{
	base.OnCreate (bundle);
	// Set our view from the "main" layout resource
	SetContentView (Resource.Layout.Main);
	// Get our button from the layout resource,
	// and attach an event to it
	Button button = FindViewById<Button> (Resource.Id.myButton);
	button.Click += async delegate {
	var table=MobileService.GetTable<Favorites>();
	await table.InsertAsync(new Favorites(){
	Hours = 2,
	Minutes = 2,
	Seconds = 1,
	User="test"
	});
	};
	}
	}
	}

view raw AndroidMobileService.cs hosted with ❤ by GitHub

However when I tried to connect to Azure, every call failed with the following error message:

“The authentication or decryption has failed.”

I was able to fix the problem by switching to a more recent Android version in the emulator.