At the start of the game, you have to turn o the power to the complex, and not long after you do so, you get a random message on the computer in the next room that reads, “There is a secret door Past the 4 bookshelves on floor 1 <EOM>.”
If you skipped through this message by accident, there is no way of rereading it. Examining the computer again yields nothing. So first off, we need to go to floor 1, in the same building the computer is in, and look for three bookshelves. Truth be told, the message was right.
On the right-hand side of floor 1, there are three bookshelves. All you have to do is walk up to the seemingly bit of metal wall, and the hidden door will just open. There is nothing more to it. Extremely easy but tricky if you missed out on what the message actually reads.
Having no way to see the message again. Even though there is a notes page in the pause menu, that is only for collectibles, not for random bits of important information that you may have missed by accident.
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