Help File Registration

Before a compiled Help (.HxS) file can be viewed, it must be registered on an end user's computer. The Help registration process associates each Help file with a specific namespace, which Windows uses to keep track of the location of all registered Help files. The namespace is usually created at registration time, and can reference one or more Help files. After registration, the Help files are accessed using a URL that follows the ms-help protocol.

Help files should be registered using Windows Installer, or a program that is compatible with Windows Installer. The Microsoft Help run-time components and registration logic are added to the installer project through merge module (.MSM) files, which are provided with this documentation. For more information, see Redistributing Help Files.

There are three basic scenarios for how Help files can be registered on a target computer, in order of complexity:

  • Single .HxS file

  • Multiple .HxS files

  • Plug-in namespaces


The HxComp and HxMerge utilities are no longer supported, though they can be acquired with the Visual Studio 2005 SDK. Instead, use the Visual Studio Help Integration Wizard or the integration tools supplied with Innovasy HelpStudio Lite. For more information, see Help Tools.

Single .HxS File

Registering a single .HxS file to a single namespace represents the simplest possible scenario. The only file that is required is the .HxS file itself. When you register a single .HxS file, it is associated with the namespace you specify. You can also specify a descriptive string and a language identifier.

Multiple .HxS Files

Registering more than one .HxS file requires the registration of a collection definition (.HxC) file, which forms the master file under which the .HxS files are registered. To improve performance, you may want to generate a compiled Help index (.HxI) file, a combined attribute index (.HxR) file, and a combined full-text index (.HxQ) file. These files combine the keyword, attribute, and full-text search indexes for each of the .HxS files, respectively. The .HxI file is generated by the HxReg utility, which ships with the Visual Studio 2005 SDK but not in VS 2008, while the .HxQ and .HxR files are generated using the HxMerge.exe utility. For more information about HxReg, see the 2005 documentation.

Plug-in Namespaces

The Help plug-in feature enables you to nest one or more child namespaces within another namespace, called the parent. Plug-ins work with namespaces that have already been registered, and are best-suited for situations that require updating and maintaining modular Help collections on the user's computer. Plug-in namespaces must be initially registered with a master .HxC file.

See Also


Collection Definition (.Hxc) File

Other Resources

Redistributing Help Files