Spatial Analyst broken by script (ArcGIS 9.3)

Discussion created by robeym on Nov 7, 2010
Latest reply on Nov 8, 2010 by robeym
I have a strange situation. The attached script runs from ArcCatalog many times without
a problem. However, there comes a time during a run when ArcGIS will say "ArcGIS has encountered a serious problem". After closing ArcGIS, Spatial Analyst does not work. No Spatial Analyst tool works.
This is the same on different PCs. Even after re-installing ArcGIS the problem is not solved.

Any ideas please?