Some screen alignment and display issues can be solved by running a simple screen alignment process, accessible through you phone's settings.
This guide will take you through the steps of realigning the screen of the HTC Fortress. You will need to perform several actions involving the phone's user interface and stylus.
With the phone powered on and at the home screen, tap "Start".
Now tap "Align Screen". This will initiate the Screen Alignment Process on your phone. Follow the instructions on the screen.