Question

I want to use SendInput via C++ to lock the computer (Windows+L). I have created simple keyDown / keyUp functions in which I use SendInput to send a VK. On keyUp, it adds the flag 0x0002

I can simulate my tab key, my windows key and now I try to lock my computer with a simulated key stroke. I send the following messages:

key down:  0x5B (win key)
key down:  0x4C (L)
key up:    0x4C (L)
key up:    0x5B (win key)

My problem: Nothing happens 🙁

Does someone know whats the solution?

Answer 1

If I am not mistaken, you will not be able to do this with SendInput() (or keybd_event()) because it simply injects the keys into the keyboard input buffer, but special key sequences like CTRL+ALT+DEL, WIN+L, etc operate at a lower layer that are interpretted by the OS before keys are put in the input buffer.

The correct way to lock the computer is to use the LockWorkStation() function instead.