Enabling Spatial Analyst
To use ArcGIS Spatial Analyst, the extension must be properly installed, licensed, and enabled.
Making the extension available
If the extension is not available, either review the appropriate section of the Administrator Library or contact your system administrator.
Note:If your organization has not purchased a license for this extension, you can evaluate it free of charge for a certain period of time.
Enabling the Spatial Analyst extension
Once the extension is installed and licensed, you need to enable it. You can then begin working with the Spatial Analyst geoprocessing tools.
Activating the Spatial Analyst toolbar
The Spatial Analyst interactive toolbar is not automatically added to your ArcGIS session by default.
To make it available, on the Main menu of ArcMap click Customize > Toolbars and choose Spatial Analyst from the list.
You should now see the toolbar as a floating window.