Error message :
DRIVER_IRQL_NOT_LESS_OR_EQUAL (i8042HDR.sys)
Problem caused by Lenovo Keyboard Driver
Solution:
UNINSTALL AND DELETE THE "LENOVO DRIVER" under Keyboards
After reboot, the keyboard will become “Standard PS/2 Keyboard”
Problem solved.
Reference:
http://answers.microsoft.com/en-us/insider/forum/insider_wintp-insider_devices/10547-driverirqlnotlessorequal-i8042hdrsys/56b1938a-995e-4b1b-ac1e-720b9b6ba5ae?auth=1