If the screen is not responding, try pressing the Home hardkey on the face of the unit. If the menu comes up, the issue is likely with screen calibration. To perform a screen calibration without using the stylus:
a. Press the Home icon hardkey button, (the physical button at the lower-right with a picture of a house).
b. Press the down-arrow hardkey until Control Panel is selected.
c. Press the right-arrow hardkey once.
d. Arrow to select Calibrate Screen and press the OK button.
e. Follow the instructions on screen to tap the center of the crosshairs in each location. Be sure to tap the exact center of the target and to hold the stylus as you would when using the device. Take care not to drag your pinky finger on the screen.
If the home hardkey does not respond, or the screen remains unresponsive after calibration, see:
How do I reboot or reset a LabQuest?
A good test to see if the screen is well-calibrated is to open the periodic table application from the home menu on LabQuest. As you tap each element in the table, you should see the details for that element. Be sure to try elements in different parts of the screen (upper-left, lower-right, etc.) If tapping an element brings up properties for an adjacent element, then the screen is not registering the correct coordinates of each tap. Should this happen, re-calibrate the screen as described above.