Background: Microsoft Compiled HTML Help is a proprietary format for online help files, developed by Microsoft and first released in 1997. CHM format is optimized for reading, as files are heavily indexed. All files are compressed together with LZX compression.
On Windows, a CHM file can be extracted to plain HTML with the command:
hh.exe -decompile extracted filename.chm
Some users are unable to open these help files. They may experience this in one of two different ways:
- Search for the file
hhctrl.ocx. This file should be in the
- Go to the Windows Start menu and select run. Then type the command:
Where <directory> is the location where
hhctrl.ocxis installed. This step will register the DLL with the ActiveX server.
Once these steps have been completed, the user should be able to open the help files.