Refund of a time barred it return...

Friends, my client was entitled to a refund but had not filed return of income.. now return is time barred. So what is the EXACT PROCEDURE to submit such return and claim refund? I visited ito and requested him to accept my return. He is not ready to accept my return and gives me excuses only... What action should I take further?? Help me please . thank you for your suggestions in advance if any