The Google Maps API server rejected your request. The “sensor” parameter specified in the request must be set to either “true” or “false”.
UPDATE: This issue can be resolved by un-checking the option Generate Random Version Number in Better Security Tweaks
UPDATE 2: When performing a search in IE or Chrome, Firefox seems to be unaffected, the results will be shown. However, if you perform a second search from within the previous search results, you will receive a 404 error. At this time there is no solution other than to deactivate Better WP Security.
NOTE: This FAQ was written based on Better WP Security 2.18