Once you have snuck into Secure Tech headquarters and learned how to stealth thill your enemies, you'll eventually find yourself in the Laboratory, but there is a big door blocking your way. You must open this door to progress.
When you interact with the Sector 2 big door, four lights will turn off above it. You must turn these back on and to green before the door will open to allow you access deeper into the lab. Around this starting area of the lab, four power switches need to be hacked to do this.
The first switch is very close to the door. From the door turn around and walk until you reach the metal railing. Turn around once more, and on the pillar to the right is the first hackable switch.
Switch two is located down a set of stairs. Facing switch one, turn around, and head back towards the lift. There will be a set of stairs to your right. Go down them, then turn around, so you're facing the stairs, and the second switch is on the wall to the right of the stairs.
The third switch is located to the right of the first switch. Once again, go down a set of stairs, and halfway into the room on the right-hand side above a desk is the third power source.
Switch four is located near the lift you came down in. Look to your left from the lift facing the big door, and they'll be three lockers. Open up the middle locker. The fourth switch is hidden in there. Once all have been hacked, the big door will openm
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