In the Book Format script line, the output type property is set to Sections, and one of the sections defined in the physical sections property has no section rule.
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Solution
•Modify the list of Physical Sections (recommended): Opens the physical sections property editor and lets you define other rules for this section.
•Change to Standard Flow: Changes the setting of the output type property from sections to standard, thus making the physical sections irrelevant.
Topic 110036, last updated on 22-Mar-2021