Lenovo Ideapad Z400 brightness problem

It happened to my lenovo z400, I couldn't adjust my screen's brightness. I've browsed and found many alternatives to solve this problem. The best solution of them all is just by executing the 'setup.exe' that can be found in c:/drivers/Intel Video Driver/9.17.10.3223. Execute setup.exe as administrator (right click and run as administrator), thats all and let it do the magic.