Board Thread:News and Announcements/@comment-24729554-20160822210308/@comment-27024938-20160824230930

Ok, I've added every code that's in my guide, however 1 code doesn't have an inscription, because I'm not sure what it's supposed to open.

This is what my guide says:

"Avoid the cameras by moving cautiously when they're turned away from you. Get to the stairs and climb to the third floor. Knock out the only guard who is on the walkways in the center, and then open the door that he's near. The code is (0666) if you don't want to hack it."

this is part of a side mission called "All In The Family", that you'll trigger during your second visit in Prague but only if you promised Otar Botkoveli to do him some favors. You need to knock out a guy called Dominik inside the Dvali Safehouse, drag his body to a storage locker outside the Dvali area and seal it.

It could be the door towards a laundry room where this Dominik guy is, although I wouldn't understand why someone would seal a laundry room with an electronic lock...