Defense Ministry: Nikoladze's Office
Once you rappel through the glass window and kill the guard, access the computer in the far right corner of the level first. Then, access the main (Nikoladze's) computer closest to the window. Immediately run back to the window and drop out, but stay near to the ledge so that you will grab hold of it and hang out with the window. Guards will enter and search the office. They will not see you if you remain hanging out the window. They will clear the room, then leave. You can now access the computer again (as instructed by HQ). Then, proceed with caution when reaching your extraction point.