Google maps API Geocode Return code 610

Question

I've been using this for quote a while in my code suddently yesterday I started getting code 610 back as a result.

http://maps.googleapis.com/maps/geo?q=rh193ge&output=json&v=2&oe=utf8&sensor=false&key=xxxxxxxxxxxxxxxxxxxxxx

{
  "Status": {
    "code": 610,
    "request": "geocode"
  }
}

I checked my key and have also generated a new key but no joy.

Any idea anyone?