Pyautogui and win32api key presses blocked in an application

  pyautogui, python, python-3.x, winapi, windows

I have to enter a large amount of data into an application so I tried doing it with help of python modules.
But niether pyautogui nor win32api is working in it. Also ctrl+c and ctrl+v are blocked when the application is running.

Any help would be appreciated. Thank you

Source: Windows Questions