Before showing a toast notification, it is important to register the manager first. The appropriate place to do it is the form's constructor. Don't forget to unregister the manager while closing the application.
There are several overloads for the Register and Unregister methods. It is essential to use the corresponding Unregister method considering which of the Register method overloads are used.
Here are listed the available Register method overloads:
This is the preferred method for registering the toast manager.
It actually registers the application using the current process file name (full exe name), adds a default Telerik shortcut name, default AUMID and internal activator (RadToastNotificationInternalActivator). When the internal activator is activated, it fires the static RadToastActivated event.
It registers the application using an internal activator, expecting the path of the executable, a name of the shortcut that will be placed in start menu and a unique id of the application - recommended string - name + GUID.
If you don't have a shortcut for your application, you will have to pass a shortcut name for it and its ID. In case you already have a shortcut created for the application, you must pass null for the shortcutName parameter and specify the application ID.
Similar to the above mentioned Register method overloads, there are two overloads that expect a RadToastNotificationActivatorBase which is actually a derivative of the Microsoft.Toolkit.Uwp.Notifications.NotificationActivator.
() where T : RadToastNotificationActivatorBase
(string exePath, string shortcutName, string aumid) where T : RadToastNotificationActivatorBase