Is this only happening on certain books or on all books. If on all books, have you checked that you have the "Folders instead of Books" option deselected in the Advanced Settings of your Microsoft HTML Help single source layout?
Colum seems to be making an assumption that you are producing Microsoft HTML Help, as the option he mentions only applies to the world of compiled CHM files.
But this question was posted in the WebHelp forum category, so one might assume that you are producing WebHelp output.
So the question we ask here is this:
What *IS* the output type you are creating? WebHelp? Microsoft HTML Help? FlashHelp?
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