WinRT gotcha – “one shot” Timer BackgroundTask does not unregister after the “one shot”

First up – sorry Jack Reacher fans, this post is not about the novel 🙂 . In my latest Windows 10 app Event Countdowns I made a very unlucky mistake. When registering its Background Task that should update the app’s tiles every 30 minutes, I used the following code:

At first glance, nothing out of the ordinary. Or so I thought. One day after the app was