Product Code does not exist; Contact System Administrator

I have brought up SRM-MDM-Catalog 3.0 on SRM 7.1, MDM 7.1.

I am able to see catalog item after the search. I selected the catalog item and click on 'Add to Cart'.

I get the error message saying

Product Code does not exist; Contact System Administrator

However the same product code is defined in SRM and MDM. I checked up the company code and corresponding product group.

How can I debugg these messages. Can any one give some tips on dealing with these error messages.

What is the Web Dynpro component that validates these messages. Can I keep break point at appropriate places.

Thanks.