You can rename any combination of the following files:
Project file (.MPJ)
contents file (.HHC)
Index file (.HHK)
Open the project.
From the File menu, select Rename Project.
To change the name of your project, edit the text in Project File Name.
To change the name of your table of contents file, edit the text in TOC File Name.
To change the name of your index file, edit the text in Index File Name.
Click OK. The file names you modified are saved with the project. For the changes to take effect, the program closes and then reopens the project.
Note: If you are creating Microsoft HTML Help, the name of the compiled HTML Help file (.CHM) is based on the project file name. If you change the project name, the .CHM file name will change the next time you compile. You can keep the old .CHM file name or assign a different one. For details, see Renaming .CHM files.