I start the Windows On-Screen-Keyboard like that:

s_onScreenKeyboard = new Process();
s_onScreenKeyboard.StartInfo = new ProcessStartInfo("osk.exe");
s_onScreenKeyboard.EnableRaisingEvents = true;
s_onScreenKeyboard.Exited += new EventHandler(s_onScreenKeyboard_Exited);
s_onScreenKeyboard.Start();

This works fine, but when I try to stop it using the following code, it does nothing:

s_onScreenKeyboard.CloseMainWindow();
if (!s_onScreenKeyboard.HasExited)
{
    if (!s_onScreenKeyboard.WaitForExit(1000))
    {
        s_onScreenKeyboard.Close();
        //s_onScreenKeyboard.Kill();
    }
}

When uncommenting s_onScreenKeyboard.Kill(); it is closed, but the problem is that osk.exe obviously uses another process called "msswchx.exe" which is not closed if I simply kill the OSK process. This way, I would end up with hundreds of these processes which is not what I want.

Another strange thing is that the CloseMainWindow() call worked at some time, but then it suddenly did not work anymore, and I do not remember what has changed.

Any ideas?

Background:
I am implementing an On-Screen-Keyboard for my application because it should work with a touchscreen. It is important that the keyboard layout matches the layout which is configured in Windows since the application will be shipped to many different countries. Therefore, instead of implementing a custom keyboard control with approx. 537 keyboard layouts (exaggerating a little here...), I wanted to utilize the Windows built-in On-Screen-Keyboard which adapts to the selected keyboard layout automatically, saving a lot of work for me.