You need to fully read what all the terminals say until a red arrow appears then you can advance to next page. This achievement can be annoying, but just wait til everything is done and take your time and you will get it.

You need to fully read what all the terminals say until a red arrow appears then you can advance to next page. This achievement can be annoying, but just wait til everything is done and take your time and you will get it.

happened to me too...

you also need to get the terminals in a continuous mission.. all except cortana

just find the terminals in order, wait until the 1st screen on the terminal turns red and
then wait until the 2nd screen appears then you can leave(start at the begginning of the
level, and find them in order).

u do need cortana on legendary
on normal and heroic u don't
sometimes on normal u do so i would suggest getting that terminal anyway