BenQ PL460 Installation Handbook page 82

Make sure that only the tip of the touch pen touches the screen.
Keep your hand away from the touchscreen, as the detectors may
detect your hand even it does not touch the screen surface.
Failed calibration
Please try with the built-in calibration tool on the Windows
operating system.
Contact the service provider to see if a calibration software is
available.
Add extender/repeater
If the touch is not working, please add a USB hub/extender.
If there is no display, please add the display port repeater
(ex.HDMI repeater).
Try with shorter cables (shorter than 3M for display cable/1.8M
for touch USB cable). If the problem is solved, please try to add
the repeater.
82 Appendix 2: basic troubleshooting checklists
Check item
Check item
Check item
Does the
problem still
Check if
exist?
completed
Yes
Does the
problem still
Check if
exist?
completed
Yes
Does the
problem still
Check if
exist?
completed
Yes
No
No
No