As I understand it, when the Windows "Hide underlined letters for keyboard navigation until I press the Alt key" checkbox is checked, when a context menu is shown via a right-click, the underlines should be hidden, but when it is shown via the Apps key or by Shift+F10, they should be shown. In C#, I have added a context menu to a third-party control by intercepting the MouseDown and KeyUp events and then showing the context menu using the ContextMenuStrip.Show method. When I do this, the underlines are not shown from either the mouse or key events, unless the user pressed Alt prior to right-clicking or pressing the shortcut, it which case they are shown in both cases. I would like to conform to the expected behavior, but I am not sure how to, assuming it is possible, using the .Net ContextMenuStrip.