Begin facing an open office. You'll be in an empty one yourself. Head to the window of the office in front of you. Turn around. To the left will be another office.  Head into the doorway of it. Turn to the small slender window facing not the hall but the office next to you. Dematerialize and go through it. You'll now be standing in front of another office. Head into the hall between the 2 brown door in front of you. Head down the length of the hall until you reach a larch concrete column on your left. Right before the column is an open door. Head into it and you're done.