There are a number of features in ArcGIS that are presented as extensions. These must be enabled through the menus to permit their use.


If you request a feature that is not enabled, you will get a message dialog similar to the one shown below:

Extension not enabled dialog


To resolve the problem, open the menu list headed "Customize" and select the "Extensions" item. A dialog like the following will appear - click the box next to the desired extension to enable it and select "Close" to exit the dialog.

 ArcGIS Extensions