Abrir un exe dentro de una ventana de .net

// defining the process and initilize it's attributes
Process p = new Process();
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.RedirectStandardInput = true;
p.StartInfo.UseShellExecute = false;

//starting notepad and put it within the form           
p = Process.Start("NOTEPAD.EXE");
p.WaitForInputIdle();

IntPtr windowHandle = new WindowInteropHelper(this).Handle;
            
SetParent(p.MainWindowHandle, windowHandle);
SendMessage(p.MainWindowHandle, WM_SYSCOMMAND, SC_MAXIMIZE, 0);

Fuente: www.codeproject.com/Questions/175884/Existing-EXE-run-with-in-a-window-form-using-c-WPF