BUG
When editing a custom tool such as import, export, or transform, Workbench does not open.
Note: The content in this article pertains to ArcGIS versions 9.x only. Later versions of ArcGIS may contain different functionality, as well as different names and locations for menus, commands and geoprocessing tools.
This is a known issue. It occurs when editing tools from the ArcCatalog browse tree if the ArcToolbox window is not open.
This only occurs when editing the tool by accessing it through the browse tree of ArcCatalog. Opening the ArcToolbox window and accessing the custom toolbox from there allows the edit.
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