There is an easy way to get copies of files from compiled Microsoft HTML Help (.CHM files) when you don't have access to the source files. You can use a special tool called HTML Help Studio to scan a .CHM file, display its components, and extract (get) copies of topics and other project-related files. (This tool is available exclusively with RoboHELP Office.)
From the Tools tab, double-click HTML Help Studio.
Navigate to the drive/folder where the .CHM file is located and double-click to select it.
The HTML Help Studio dialog opens. It displays a list of files that are included in the compiled .CHM file. Everything is organized according to the folder structure used in the project source files.
Folders that display plus boxes
contain files. Click the plus box to open the folder and find out what
files it contains.
To view a file, select it from the list. Its content is displayed in the pane at the right side of the dialog.
Note: For certain types of files, the File Download dialog opens (just like in Internet Explorer) and you can choose to open or download the file.
Use the buttons across the top to navigate.
Extract the files you want to use from the .CHM by doing one of the following:
To extract a single file, select the file and
click Extract .
To extract all files in a folder, select the folder
and click Extract .
To extract all files in the .CHM, click Extract and select All Files.
In Extract To, select a destination for the file(s).
If the destination folder (where you are extracting to) includes files with the same names as the ones you are extracting, select Overwrite Existing Files.
Tip: If you don't want to overwrite existing files, create a temporary destination folder and save the extracted files in this folder. After you've had a chance to review them, you can import them into your project folders.
Click Extract.