>>>>>In the other message, you said lock the keyboard, but this is locking all windows. Is that the same thing?
>>>>>
>>>>It prevents any intervention for the application (the user can do nothing with the application, but can work in Office and do other stuff).
>>>
>>>I don't understand the usage. What is the parameter when it is not 0?
>>
>>If you pass .T. it locks the window, if you pass .F. it unlocks it.
>>
>>tlLock implies that the parameter is logical type (True or false)
>
>I thought handles were numeric.

Yes, handles are numeric. But the method ReallyLockScreen is used with logical parameter. If you just want to use this Windows API pass 0 to unlock and windows handle (thisform.hwnd) or _screen.hwnd to the function.