MS Help 2.x‎ > ‎

H2 Info

MS Help 2.x is the help system used by Visual Studio 7.0/7.1/8/9 (VS 2002/2003/2005/2008) and also by Borland/Embarcadero compiler help.

MS Help 2.x was announced at WinWriters on March 5, 2001.

MS Help 2 History

The main components of MS Help 2.x engine are: hxds.dll and hxvz.dll
Installed to: C:\Program Files\Common Files\Microsoft Shared\Help\
Both files are COM so require registration.

Hxds.dll - Microsoft Help Data Services
Hxvz.dll - Microsoft Help Visuals (Visual components such as TOC and Index)


DLL VersionsRelease DateReleased with Products
2.0.9???.0Mar-2001First public disclosure of Microsoft Help 2.0 by Shane McRoberts (MS) at WinWriters 2001 conference. MVP Paul O'Rear (now MS) and MVP Cheryl Lockett Zubak also gave presentations on MS Help 2. There were several Alpha and Beta drops throughout 2001.
  • Visual Studio .NET 2002 (v7.0)
  • .NET Framework 1.0
  • Office XP (Developer edition)
  • MSDN Library - Updated to Help 2.1 with the release of VS 2002

Note that 9466 is also the same build number for VS and DExplore (H2 viewer).

  • Visual Studio NET 2003 (v7.1)
  • .NET Framework 1.1
  • BizTalk Server 2004 Standard Edition (I've never seen this)
  • MSDN Library - Updated to Help 2.2 with the release of VS 2003

Appears to fixed some of the disappearing TOC problems.

  • Visual Studio 2005 (v8.0)
  • MSDN Library 2005 - Updated to Help 2.5 with the release of VS 2005
  • Microsoft Document Explorer 2005 **

This version now supports plug-in order. See "TOC Update Whitepaper" H2 FAQ
Also MS now advise we plug our 3rd party collections into MS.VSIPCC.* instead of MS.VSCC.* (with VS 2005 ms.vsipcc.v80 collection is plugged into the ms.vscc.v80 base collection). This keeps the 3rd party plug-ins together so they can be easily isolated.

Also HxConv.exe (used to convert HTML Help projects to MS Help 2.x projects) no longer supports conversion of .CHM files (converting .HHP files is still OK). See H2 FAQ for more info.

** Although this item appears in Add/Remove Programs, DExplore can still only be installed by installing a product such as MSDN Library 2005. Note if you wanted to repair H2 corruption you could go to this item in Add/Remove Programs, run it and select REPAIR. Note also that to uninstall H2 completely you need to uninstall all products that use H2 as well as this item.

Note: Later versions of Technet also install MS help 2.x engine.

MSDN Library

MSDN Library ships quarterly (Jan, Apr, Jul and Oct).

The Jan 2005 MSDN shipment states: This edition of MSDN library is the last edition that will automatically integrate in VS .NET 2003 and last edition that includes documentation for both VS 2003 and .NET Framework 1.1. Subsequent editions of MSDN Library will be designed to integrate with VS 2005. Also future editions of MSDN Library will install side-by-side. ie. Jan 2006 MSDN Library will install for VS 2003, and April 2006 MSDN Library will, or later, will install for VS 2005.


One user found that instabilities with Help 2.1 (disappearing TOC) were fixed by updating to Help 2.2 (ie. by installing .NET Framework 1.1 SDK or latest MSDN Library). However the MS Help team don't recall fixing any major bugs in 2.2. Hey if it works that's the main thing.

MS Help 2 - Getting Started

Microsoft Help 2.x SDK

The Help 2.0 SDK (also known as Help 2.0 Workshop), is required to compile your help source to Visual Studio compatible help (.HxS) files. It is important to note that MS Help 2 is designed primarily for Visual Studio help integrators. It is not for creating general application help.

How to Install Help 2.x SDK

VSHIK = Visual Studio Help Integration Kit (AKA Help 2 SDK)

These are all free downloads.

  • For VS 2002 (version 7.0) download VSHIK 2002 (Version 2.1) 
    VSHIK 2002 Download
  • For VS 2003  (version 7.1) download VSHIK 2003 (Version 2.2). 
    VSHIK 2003 Download
  • For VS 2005 (version 8.0) download Visual Studio 2005 SDK.
    For VS 2008 (version 9.0) download Visual Studio 2008 SDK.
    This was formally called the VSIP SDK but now the VS SDK contains the Help 2 SDK (version 2.5).
    • VS 2008 SDK 1.0 download --
    • VS 2008 SDK 1.1 download --

What does Help 2.0 SDK Install?

Help 2.0 SDK installs the following:

  1. Help Compiler.
  2. Help command line utilities - HxConv.exe, HxMerge.exe etc.
  3. Help Workshop (integrates into Visual Studio .NET shell).
    For VS 2005 and later the SDK now installs Innovasys HelpStudio Lite.
  4. MSI modules used to integrate your help into VS help
  5. Help SDK documentation.
If you use a non-msi registration solution such as H2Reg then MSI modules wont be required.

Help SDK only installs on systems containing Visual Studio .NET. However if you have your own MS Help 2 authoring program (such as FAR HTML or Virtual Media's XDK etc) then it is possible to Install VSHIK without VS .NET.

  1. VSHIK 2002 (V2.1) is compatible with VS .NET 7.0 (2002)
  2. VSHIK 2003 (V2.2) is compatible with VS .NET 7.1 (2003)
  3. Help 2 SDK (V2.5) is now installed with "VS SDK" and is for VS .NET 2005.

Please install the version that matches your VS version. All versions of Help SDK can coexist on the same PC. If VS is not installed then install the later version. All versions are much the same except for documentation updates and VS compatible MSI modules.

About MSI Modules

The MSI modules are used to create installation packages that integrate the help you create into Visual Studio .NET help. VSHIK 2002 contains MSI modules compatible with VS .NET 2002, VSHIK 2003 contains MSI modules compatible with VS .NET 2003, etc.

Using the MSI modules can be very complex. Many developers find it much easier to ignore the MSI modules completely and instead install and register help content using their own installation tools, plus the non-MSI registration tool such as H2Reg.

MS H2 Runtime

MS Help 2.x runtime files must be installed before you can view MS Help 2 collections. A runtime standalone installer (like hhupd.exe for HTML Help 1.x), will not be made available as previously planned. Currently the only way to get the H2 runtime files onto a PC is to install one of the following Microsoft applications:

  • Visual Studio .NET (Express version is free)
  • MSDN Library (must be new H2 based one)
  • Tech Net (must be new H2 based one)
  • Microsoft Office XP Developer
  • Microsoft Office 2007 - Only some of the Help 2 files are installed for Office 2007. HxDs.dll is installed but not DExplore or HxVz.dll which contains the visuals (TOC and Index controls) since Office 12 has it's own custom viewer.

Note that early versions of .NET Framework SDK (1.0, 1.1) also installed the H2 runtime. This is probably the only free method of installing the runtime.


Visual Studio Express (basic version of VS) is a free download. Although you probably can't ship this with your software to customers, a small team of tech-writers who only want the H2 Runtime could download and install this from the MS web site.

Install VSHIK without VS .NET:

Officially, you must have VS .NET installed to install Help 2 Workshop. Unofficially, you can tweak the VSHIK install (VS 7.x) or VS 2005 SDK (VS 8.0) so that it skips the VS .NET dependency check. Thus tech writers and build machines etc. do not need a copy of Visual Studio.

To setup your PC for MS Help 2 authoring without installing VS:

  1. Install the MS Help 2 Runtime. 
    EG. Install MSDN, TechNet or .NET SDK (see Runtime info above).
  2. Download VSHIK (VS 7.x compatible Help SDK) and follow the instructions on the FAQ page

    or download VS 2005 SDK (VS 8.0 compatible SDK) and follow the instructions on the FAQ page 

Note: For VS 7.x the free Microsoft Workshop authoring tool which runs only in the Visual Studio .NET shell will obviously not be available (since you are not using VS). However other H2 authoring tools such as our shareware tool FAR HTML will work.

Unofficially Microsoft have welcomed this installer tweak.

MS Help 2 - News
  • June-2008: Free MS Tool Namespace# 2.0

    Paul O’Rear [MS] (was a Help MVP) has got his Namespace# 2.0 tool released on the MS web site. A nice MS Help 2.0 diagnostics tool that goes beyond the features of Namespace.exe (free tool with VS SDK). It allows you to view all Help 2.0 namespaces on your system and drill into the files and information associated with each namespace.

    Great tool. Very similar features to our FAR H2 Utilities and reads Namespace information a little faster than FAR. Requires .NET 2.0 runtime (which you should already have if VS is installed).

  • Oct-2005: Innovasys to provide H2 Workshop for VS 2005

    MS have removed the free bare bones H2 Workshop from VSHIK. When VS 2005 RTM is released a new VS 2005 SDK will be made available containing a light version of Innovasys HelpStudio. This agreement allows the MS Help team to concentrate on AP help development, while providing users with a much better free authoring tool.
  • Dec-2004: VS 2005 SDK

    VS 2005 does not have a VSHIK download. Instead please download VS 2005 SDK (formally VSIP SDK) as this incorporates the Help 2 SDK.
    See Download locations above.

  • Nov-2004: Plug-in Order

    MS have released a document for VS 2005 integrators. It describes a new feature of the Help 2.5.x engine which allows control of plug-in order. Plug-in order is achieved by adding IDs to your Master TOC and to the TOCs that plug into that. 
    See H2 FAQ

  • 18-April-2004: MS Help Registration Wizard

    MS have released a Wizard (Beta) for creating registration info for Help 2 Collection files and Help 2 MSI installations. This has been a very complex and confusing area so users should be very pleased. Wizard Homepage. Remember if you don't like using MSI to register like us, we have a non-MSI registration solution called H2Reg.

  • 19-Aug-2003: VSHIK 2003 Update now available

    VSHIK 2003 update now available: This version contains some minor documentation fixes only: The front page had bad links to the two Word WhitePapers  (which no longer exist in VSHIK 2003 as they are now integrated into the body of the help 2 documentation). Also this collection has one less Title "vshikcommon" (vshikcommon.HxS) which from memory simply contained duplicate info to one of the other Titles.

  • 28-May-2003: DExplore COM Interface

    We are please to provide new documentation on the DExplore.exe COM Interface, which provides rich support for controlling the MS H2 Standard viewer.
    See DExplore COM Interface

  • 13-May-2003: VSHIK 2003 now available

    VSHIK 2003 now available: This version is compatible with the latest Visual Studio update (VS .NET 7.1)

  • 9-March-2003: H2Viewer

    We are pleased to announce the release of H2Viewer. A replacement viewer for MS DExplore.
    See H2Viewer Home Page

  • 10-Jan-2003: MS say No longer releasing Help 2 redistributable

    MS announce that the Help 2 runtime and viewer will not be released for redistribution. Help 2 is now supported only for extending the Help content in Visual Studio .NET. 

  • 24-May-2002: VSHIK Update

    There is a new VSHIK download containing a few documentation fixes only.

  • 22-Apr-2002: Helpware releases H2Reg

    We are please to announce the release of H2Reg. An installer program extender that allows you to register/unregister MS Help 2.x Collections: Namespaces, Titles, Plug-ins, and Filters without using MSI (Microsoft Installer).
    See H2Reg Home Page  

  • 11-Apr-2002: New MS Help 2 Ships as VSHIK 2.1

    The MS H2 SDK is now available on the MS website. It is available as the new VSHIK (Visual Studio .NET Help Integration Kit).

    FAR users please note: I have just uploaded FAR 3.2 which is fully compatible with this new SDK release.  

  • 28-Dec-2001: MS Help 2 Delays

    MS Help 2 timeline has slipped. Release date will be sometime 2003.
Tutorials & Articles
Further Reading

H2 Authoring Tools

H2 Registration Tools

  • H2Reg Shareware - H2Reg is an install program extender that allows you to register/unregister MS Help 2.x Collections: Namespaces, Titles, Plug-ins, and Filters without using MSI (Microsoft Installer).

H2 Viewers

Other Resources
  • MS H2 FAQ - Helpware has started an H2 FAQ page.