Problem: The Spatial Analyst Functional Reference is not accessible from the ArcGIS Desktop Help system
** This issue has been resolved in ArcGIS 9.0. **
In some cases, the Spatial Analyst Functional Reference is not launched from the link directly under the Spatial Analyst documentation in the contents of the ArcGIS Desktop Help system.
This is a known issue with ArcGIS 8.2 and 8.3.
Solution or Workaround
In previous versions, there are two work-arounds to this problem. Access the Spatial Analyst Functional Reference from the Raster Calculator within the Spatial Analyst toolbar or access it directly from disk.
1) Right-click the Spatial Analyst toolbar and click Raster Calculator.
2) Click 'About Building Expressions' and click the link 'Functional Reference' for Spatial Analyst functions.
1) Navigate on disk to the %ARCHOME% directory, typically C:\arcgis\arcexe82\, and click the Help folder.
2) Double-click CommandRef.chm to launch the Spatial Analyst Functional Reference.
To make it more easily accessible, create a shortcut on the desktop.