In ArcGIS, if I receive the error message "Tool not licensed", what should I do?

When selecting an ArcGIS Desktop extension tool, you might see the following error message:

"TOOL NOT LICENSED
Unable to Execute the Selected Tool.
You do not have the necessary license to execute the selected tool"

To correct this error, check the following:

• Make sure you have turned on the appropriate extension: In ArcMap, click Tools, and then select Extensions. In the Extensions dialog box, check the extension you wish to use, and then click Close.
  
  
• Enable the appropriate toolbar: In ArcMap, click View, and then select Toolbars. From the menu, check the toolbar (set of tools) you wish to use.
  
  
• Verify that your ArcGIS product level is set to ArcInfo: If you have paid for an ArcGIS ArcInfo license, confirm that your product level is set to ArcInfo and not ArcView. The tools within the Spatial Analyst extension are available only with the ArcInfo license. Likewise, other extensions, such as 3D Analyst and Geostational Analyst, also contain some tools that require an ArcInfo license.

  To see your ArcGIS product level, look at the top title (in blue) of the ArcGIS window. It might read, for example, Untitled - ArcMap - ArcView. For help changing your product level, see In ArcGIS, how do I change the product level?

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