I recently encountered a PDF export problem that plagued me for months. I was trying to export a book containing roughly 50 InDesign documents. The last 25 or so documents contained scanned engineering drawings placed as graphics into the InDesign documents. When I tried to export a PDF from the InDesign book file, the PDF would seemingly be exporting just fine… until InDesign reached pages with some of those scanned images. Then it seemed to randomly hang. Fortunately, I finally found the source of the problem, as well as a fix.
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