HP 815MFP - Manual (Page 59)

hp designjet 815mfp & scanner 4200 53
the problem is with the interface language
if the user interface is not in the correct language
When you installed your scanner system, the wrong language was
installed in the final step.
You need to change the interface language. See how do I change
the scanner system interface language? on page 45.
the problem is with the touch screen
if you have problems pressing buttons on your screen
You need to re-calibrate your touch screen.
1. Press the Quit button and select Exit to exit your
scanner software.
2. On the active desktop, select Calibrate Touch Screen
and follow the instructions provided.
Calibrate your touch screen from the same position in which you
would use it when working with your scanner system. You need to
do this because the angle at which you use your screen may affect
performance.