That depends on the single source layout you choose. If you
have chosen WebHelp or FlashHelp, you get a number of files that
all have to reside in the output directory for the help system to
open and display properly, plus some subfolders. If you generate a
Microsoft HTML Help output, you get a standalone .chm file.
If generating an output is the step you are missing, expand
the Single Source Layouts folder in RoboHelp's left pane,
double-click on the layout you want, and complete the dialog.