In this set of videos, Matt Risinger takes his crew out to a one-year-old lake house to examine windows that were already leaking. The Rx called for a full dismantle and re-install using his proven materials and techniques.
As Risnger notes in this blog post:
The first step in installing these correctly was to remove the windows and all the flashing that was incorrect. We want to start back at the bare rough opening. This builder was using Huber Zip sheathing that already has a weather-barrier integrated into the sheathing.
You want to assume that any window has the potential for leakage so making a good waterproof sill is a top priority. I also like to slope the 2x sill by about 5% so that drainage is built-in before I apply my flashing. We used a Sawzall to cut the jamb then shimmed under the 2×4 sill to give a positive slope.