Showcase is installed with several material libraries. You uninstall Showcase itself from Windows Control Panel as you would other applications, but you also need to expressly uninstall the material libraries.

To uninstall the Showcase material libaries:

• In Windows Control Panel, open Uninstall / Add or Remove Programs.
• Select any entry whose name begins with "Autodesk Material Library" and click Uninstall / Remove.
• Repeat the previous step until all material libraries are uninstalled.