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Help Command-Line Programs
Several command-line programs are included for Microsoft Help support in the Visual Studio SDK. The files reside in the <Program Files>\Common Files\microsoft shared\Help 2.0 Compiler directory.
Microsoft Help compiler, used to create compiled Help (.HxS) files.
Microsoft Help registration utility, used to register Help namespaces and aliases.
Microsoft Help index merge utility, used to merge full-text and combined attribute indexes.