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MJ's Diagnostics

MJ's Diagnostics is a small utility that reports if all the HTML Help runtime & Workshop (compiler) DLLs are installed and registered to the correct locations.  If you have compiler crashes, and crashes when simply opening a CHM, or when searching from the CHM search tab, then this utility will help sort out rouge DLL problems. 

The problem: Some vendors instead of installing HTML Help Workshop (help compiler), install compiler DLLs (a subset from an old Workshop) and register parts to non-standard locations. Suddenly HATs and .CHMs are crashing. The fix is to reinstall HH Workshop. Run Workshop once. Run the report again. Email me if you need help.

See also: Other HTML Help Problems


Cost: Freeware
Author: Helpware
Distribution: Do not distribute
Ethics: We ship clean software. No adware. Just a simple diagnostics tool to help you fix your system.

  • 2014-10-01: MJ's Help Diagnostics Version 
    For Windows XP/Vista/Windows 7/Windows 8 etc -- 64 bit & 32 bit Windows
  • 2007-09-08: MJ's Help Diagnostics Version 2.7.2 
    For pre-Windows XP - 32 bit Windows only.

Installation & How To

Unzip the utility to a folder with write permissions.
Run the MJsDiags exe and generate a report. Important information is highlighted. 
If you see errors reported re-run MJsDiags as an administrator and use the "Register Help DLLs" page fix registration errors.
You may need to install HTML Help Workshop (MS HH compiler) if not installed. Default install location: 
C:\Program Files (x86)\HTML Help Workshop\

Change Log:

V1.0 2001-06-06: Original upload.
V2.0 2002-01-20: Reports in HTML format. Now also checks HH Workshop and MS Help 2.x. Also reports NT Admin privileges.
V2.1 2002-08-08: improved method of finding the Workshop folder.
V2.2 2005-02-07: Added Refresh Registration checkbox to force re-registration of HH DLLs by choice. Now does unreg before any registration to fix a bad install by MS. Now reports HH registry settings the affects the way HTML Help works.
V2.3 2005-04-23: More reporting about special registry settings. ie MS Security patch settings.
V2.4 2006-05-15: Updated. More diagnostics. Added HH Diags Home Page to web site.
V2.5 2006-06-11: Minor update. When reading registry items it now checks the data type (fixes access violation on users machine).
V2.6 2006-08-26: Minor update. Fix resize problems and detect HH compiler files even when VS has only installed HHA.dll and itcc.dll but not full Workshop UI (hhw.exe).
V2.7 2006-12-29: Elevated the executable for Vista.
V2.7.2 2007-09-08: Update documentation -- UrlAllowList= bug has been fixed by MS.Known 
V3.0.2 2014-09-10: Now supports Windows 64 bit OS. Also added check helpware site for latest version of MJsDiags
V3.0.3.92  2014-09-19: Tweaked the report format. Color highlighting of errors.
V3.0.4.95  2014-09-29: Now reports if EXE/DLL is 32 or 64 bit. Highlight policies enabled. Allow for all HH DLLs being 32 bit even in the 64bit area.
V3.0.5.96  2014-10-01: Improve checks for valid Workshop folder.