Search for empty paragraph marks by searching for two «End of paragraph» marks, and solve each instance using the paragraph style's before - and - after spacing. (electricbookworks.com)
Replace double paragraph marks (which mark the actual paragraphs) with a marker (something that doesn't occur like * X * X * X *). (dealsagar.com)
Never use empty lines or paragraphs to create space in your books (line spaces created by typing paragraph marks). (electricbookworks.com)