Some companies do have a policy of not giving any feedback for such calls. Since they believe that the process undermines the credibility of the employee. Secondly they will not even spell out an opinion, since they believe that merit is an opinion. Though IT companies are very open about providing background information on any verification sought and this process is very much prevalent in almost all IT companies and also companies located in IT hubs such as Hyderabad, Bangalore, Gurgaon and major cities, since some HR practices of IT companies do rub off on them. This does become a challenge when a company has a policy of not responding to background verification.
I used to work for a fortune 500 Multinational in its global headquarters in HR. The company neither wanted a reference nor was willing to part with any former employees details and it was a strict policy not to talk about a departed employee to anyone. It was surprising for me. But, I did realise some companies do have such a policy. Under such circumstances, there is nothing much one can do. I would suggest to inform your HR that your past company has such a policy of not entertaining background verification. In any case the onus lies on your HR to obtain the verification and not on you. So why bother.