Hi, Folio Builder is not part of InDesign CC 2015. See the following article Digital Publishing Solution Help | Install tools for DPS 2015 "You can use InDesign CS6 or later to export article files for use in DPS 2015 apps. However, if you want to use InDesign to create DPS folios, use InDesign CS6, CC, or CC 2014. You can install multiple versions of InDesign if you want to work on build DPS folios and export articles for DPS 2015."
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