Really strange problem, i’m using the Pro version (2.3.6) of this on wordpress 4.3, and although the map is fully functional and displaying all the markers and categories on the site, in the dashboard / admin panel, there is no map data – supposedly not even a map, no locations, no markers, nothing. Whats going wrong?
I am having the same problem... It is very unpleasant.
Anybody having a fixing idea?
Reason is that you're running a old version of the plugin and after upgrading 4.2, this problem is coming. Please update with latest version and this issue will be resolved.
You can get latest version of lite version 3.0.4 here - https://wordpress.org/plugins/wp-google-map-plugin/
and Pro version here - http://codecanyon.net/item/advanced-google-maps-plugin-for-wordpress/5211638
I hope it helps you.