The Google Earth plugin has been deprecated, but has already stopped working for many browsers including Google Chrome. The error messages is a default message for when the plugin fails to load. For now, Chrome has a work around, but these require the user to change Chrome settings. Below is the supported browser page from Google (notice Chrome support stops at 39; current version around 42) and Google Earth Blog's current work around for Chrome. As of May 3, Firefox asks user if they want to load the Plugin, Chrome was the same way until version 42. IE has needed a compatibility <meta tag> since IE10.