The Desktop Help system fails to open when using the Help menu > ArcGIS Desktop Help option in ArcMap or ArcCatalog.
This is limited to the Windows Server 2003 (32-bit) operating system (OS) only, standard installation and all service packs (for example, Windows Server 2003 R2). This issue is not reproducible in other operating systems.
The Desktop Help system (installed Help) is a merged CHM Help system. To launch a (compiled help system) CHM successfully you need to access the Windows hh.exe file. The Windows Server 2003 32-bit operating system seems to react differently to the hh.exe than other operating systems. The cause has been narrowed down to the following: The software menu does not handle the hh.exe file in a way that supports this OS.