problem with AccessibleRole - Different behavior in design and at runtime

Question

I have a windows forms application. It contains a menu item called CheckMenuItem of type Forms.ToolStripMenuItem, that should behave as a checkable item, when the properties Checked / CheckState set. This works properly for a seeing person, but not for a blind one using the screen reader NVDA.
When I focus CheckMenuItem in the forms designer, NVDA presents it properly. That means, that it is spoken as “CheckMenuItem Checkbox not activated” or “CheckMenuItem Checkbox activated”.
When I start the application the same screen reader announces only “CheckMenuItem”.
I guess, I forgot some initialization work. But which one?

Answer 1

The main point is, that the behavior is different in UI-Designer and in the running app.
So the point isn't the screen reader, but the App.