After you open the filing cabinet, look at the sticky note inside the left drawer.
Hint 5
The password is KLEROTERION, but it won't work until you read the note for yourself. (A kleroterion, by the way, is a device used in ancient Athens to randomize jury selection. It's pretty cool, if you want to check out the Wikipedia entry: #h+https://en.wikipedia.org/wiki/Kleroterion#h-)