During the Plant chapter in the Extreme and European Extreme modes, you have to wake up the President. To do this, toss a stun grenade at the wall directly in front of the elevator. When he wakes up, go to the wall and put your back against it. After that, find a location where there are no crates and keep knocking. When he gets there, run to the place where you have to shoot out the Nikita. That will distract him and move him from the electric box.