Apologize for our delay reply.
Our developer have found out the reason for this issue. Some invalid bounding
boxes are contained in the bounding box list. To resolve this, please download the latest bounding
boxes list file from ap.thinkgeo.com:5001/fbsharing/WOgrzf04,
and replace the zipBBX.txt in US geocoder data folder with the downloaded one.
Hope this would be helpful and if the issue
still persisted, please feel free to let us know.