ammap not showing visitors

The ammap does not show any visitor’s location/country, with the exception of your location. And the icon for the map displays question marks under it. I updated the “old data” on settings page and reset everything without success. I replaced the geoip.inc file and still it does not work. Is there anything else I can try? Otherwise everything is working well and it is a very nice plugin.

http://wordpress.org/plugins/count-per-day/