How can you be stuck on this for weeks? Just check the cameras, display the hidden files in the file explorer and look at them, and type the names of the important characters in the email search bar (Emilie, Robert, Lea, the name of the cop and the lab I can't remember but who appears in the clues at the top right) and read them. With all that you'll have more than enough to shut down the computer and continue. You don't need 100% of the evidence to finish this, just 10 clues out of 30 are needed if I remember correctly.
Btw, all of this is explained in the dialogue just before.