Hello! I´m facing a problem when trying to close a Windows Explorer (not Internet Explorer) window through another application, using the "Process.CloseMainWindow()" method; because it doesn´t close the Explorer window, it tries to close the full Windows (Operative System), by the way, Windows XP. The code is as follows: [DllImport("user32.dll")] static extern int GetForegroundWindow(); [DllImport("user32.dll")] private static extern UInt32 GetWindowThreadProcessId(Int32 hWnd, out Int32 lpdwProcessId); public String[] exeCommand() { try { //Get App Int32 hwnd = 0; hwnd = GetForegroundWindow(); Process actualProcess = Process.GetProcessById(GetWindowProcessID(hwnd)); //Close App if (!actualProcess.CloseMainWindow()) actualProcess.Kill(); } catch { throw; } return null; } Suppose that the "actualProcess" is "explorer.exe" Any help will be appreciated!! Salutes!