Halo: The Master Chief Collection - Halo 2 - Enamored - Halo 2: Activate Terminal 7 on Regret. This achievement is fairly easy to unlock.
On the mission Regret, after the first elevator ride you will enter a large room filled with enemies. The terminal is located on the middle floor on the left side of the room.
Run over and interact with it and your achievement should pop! Enjoy!