When attempting to register or register and display Google Maps service in the Geospatial or Webmap Publisher Portal the user is met with the message "Google Maps is not enabled. Please contact your administrator" and the Google Maps data source is not registered. When the user reviews the Portal instance configuration via the Administration Console the Map Service Type of 'Google Maps' is shown as 'visible' by default. Why then is the Google Maps service not visible or enabled in the Portal?
To resolve this the user is required to navigate to the 'web.config' file of the portal instance and set the 'GoogleMaps enabled tag value equal to 'true' as it is 'false' by default.
For further information refer to:
Google Maps API is enabled only when enabled is set to "true".
For configuring Google Maps API Key (apiKey attribute) refer to https://developers.google.com/maps/signup
<GoogleMaps enabled="true" apiKey="" />