"Unexpected end of json input"

[#1]

Hi,

I created NPrinting objects in my qvw file and deployed into access point. When I click on NPrinting object it is displaying this error 

"Unexpected end of json input".

I opened the access point in chrome Version 50.0.2661.102 m (64-bit)

Nprinting Server version is 16.3.0.0(SR3)

Qlikview version is 12.0.20100 SR2

Please tell me how to solve this. Do I need to change any settings in NPrinting Extension object scripts or any settings in NPrinting Server?

Thanks in advance.