FAR HTML 5 A collection of advanced help authoring & file utilities for Windows and Visual Studio help.
 MshcMigrate Migrate .chm (HTML Help) and .HxS (VS 2002/2003/2005/2008 help) to VS 2010/2012 help (aka MS Help Viewer).
 H2Reg Register and integrate into VS 2002/2003/2005/2008 help collections (.HxS, MS Help 2) without MSI.
 H2Viewer MS Help 2 alternative viewer and utilities. Free for personal use.
 H3Viewer MS Help Viewer 1.x alternative viewer (VS 2010 help viewer). Free for personal use. 

See also 

 MJs Diags Free tool to validate all MS HTML Help runtime and workshop DLLs. Fixes strange crashes due to corrupted systems.

HelpMaster Publication Series - Get on the fast track to leaning.