I have looked via developers tool kit and found 4 files
npf_includes/prebuilt_fields/UPC/Your_Admin/includes/languages/english/npf_Definitions/ups_isbn.php
npf_includes/prebuilt_fields/UPC/Your_Admin/includes/npf_includes/npf_sql/upc_isbn.php
npf_includes/prebuilt_fields/UPC/Your_Admin/includes/npf_includes/npf_sql_array/upc_isbn.php
npf_includes/prebuilt_fields/UPC/Your_Admin/includes/npf_includes/npf_templates/upc_isbn.php

and removed the code mentioning the UPS and still get an error.

I have also edited includes/classes/google_base.php and also get the same error.

Where can I find this in the Table?