Go through that door and around the corner and shoot out the exit sign from a distance. Then sneak up to the lighted area and watch the guy working on the door's key pad with your EEV. He talks to himself and says the door code to the Vice Presidents office and then he'll come back to you and go into the closet across from the exit sign. Then you hack the computer sitting on the top of the desk in the security booth. If you shoot out the lights in this hallway, make sure you do it with the pistol from a distance or the guards in the booth will come out shooting.
I could walk you through the entire mission, but it would be a lot of typing, so I hope this helps a little.