How do I determine why all outlets on a breaker stopped working, but the hot-grounds are still 120V?

Edit: Is there a way to find an open neutral between the working breaker and the first nonworking outlet without cutting open the wall. It is a pretty straight shot between the 2 with no junction boxes or known splices between.

3 outlets on 1 breaker, all hot-ground = 120V, neutral-hot and neutral-ground register nothing using a Sperry voltage tester ET6204. Using Ideal circuit tester 61-035, all 3 lights light up in all 3 outlets (top and bottom).
I identified which outlet is first. Breaker hot-neutral is 120V.
A window was recently replaced near the first outlet in the line. Electrical line runs barely under window in wall. Window attachment screws are in wall very near outlet.
What am I looking for and could a window screw have caused the issue?