I've noticed in my telemetry data that the following code sometimes results in an exception "System.Exception: Element not found. (Exception from HRESULT: 0x80070490)"
var notifier = ToastNotificationManager.CreateToastNotifier();
var notifications = notifier.GetScheduledToastNotifications();
The code is run inside a Windows Phone 8.1 (WinPRT) application on a background thread and the exception is thrown quite sparsely.
Any ideas what might be causing this or additional information I can provide?