杀死Windows运行窗口（win + r）

Question

我正在使用Windows制作WPF c＃app，但是我无法杀死运行窗口(win + R)。我做错了什么？

    Process process = Process.Start("explorer.exe", "Shell:::{2559a1f3-21d7-11d4-bdaf-00c04f60b9f0}");
    //some kind of program
    process.kill();

编辑：throven错误是：

Exception thrown: 'System.InvalidOperationException' in System.dll

Additional information: Cannot process request because the process has exited.