EDU09 calibration failure


I have tried to calibrate the EDU09 with my PC and the following error message appears.

Calibration results:

CH1 offset at 5v/div : 157 OK
CH1 offset at 1v/div : -30 OK
CH1 Y-position low 0
CH1 Y-position mid 0
CH1 Y-position high 0

Please can someone tell me why the calibration is failing and how to solve it
Thank you


Please see these threads for a solution: