Authorization errors for query_view_data web service

We have set up the query_view_data web service as described in this article: https://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/docs/library/uuid/b5536a7f-0d01-0010

However, when I attempt to test this service via the web service navigator I get a fault code of "Authority Check Failed".

I have searched forums and blogs but can not find any info for this. Any advice would be very appreciated.