You should set this property only if you implement your own help provider class (an advanced feature). A help provider can read data from a help source and provides methods to get a help topic list, to get a dictionary of context ids and help topics, to open help in an external window, to get a topic URL that can be displayed in a C1DynamicHelp control, etc.

There are two built-in help providers in C1DynamicHelp: ChmProvider and NetHelpProvider which are used automatically when the HelpSource property points to a .chm or .html/.htm file correspondingly.