Disable window from calling SetForegroundWindow

Question

I have a serious problem on my work machine with a third party software window stealing keyboard focus, using a winapi monitor tool i detect that whenever the windows steal focus it first call SetForegroundWindow.

While searching about, i have found the winapi LockSetForegroundWindow, wow i thought i had solved the problem, however, LockSetForegroundWindow blocks me from activating any other window.

I also found that would be possible to 'block' the window from calling SetForegroundWindow using a hook, but i have no knowledge about hooking, would like to ask if there's something else i could try.

Answer 1

Usually calling SetForegroundWindow() isn't bad. Since Windows XP, there is a lock that no program do this without being allowed to do this. Read the docs: https://learn.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-setforegroundwindow

This are the exceptions:

• The process is the foreground process.
• The process was started by the foreground process.
• The process received the last input event.
• There is no foreground process.
• The process is being debugged.
• The foreground process is not a Modern Application or the Start Screen.
• The foreground is not locked (see LockSetForegroundWindow).
• The foreground lock time-out has expired (see SPI_GETFOREGROUNDLOCKTIMEOUT in SystemParametersInfo).
• No menus are active.

But when the third party tools uses AttachThreadInput(), it bypasses all these checks.

Just delete this "bad" software. Contact the developers.