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cedi editoração 01
cedi editoração 01
Participant
February 10, 2025
Answered

Apple Books validation error for EPUB

  • February 10, 2025
  • 3 replies
  • 1027 views

Hi,

 

I'm trying to upload an Epub to the apple store as I've been doing for years, but now I'm getting this error:

ERROR ITMS-9000: epub_igualdade_racial_7ed.epub: OEBPS/content.opf(28): [OPF-027] Undefined property: 'pageBreakSource'.

The pageBreakSource export option is a new feature added in the 2025 version. It's manly for epubs based on a printed version. I can validate the Epub with no errors in epubchecker. I don't want to create an extra epub only for Apple. Is anyone getting this same error?

    Correct answer Laura Brady

    You could simply add a page source. This can now be done at export by adding an ISBN to the EPUB export wizard, on the first panel of the export suite of options. The main issue here is that InDesign is exporting it with specific metadata that some vendors are rejecting. To fix it, add this to the OPF of your ebook: <dc:source>9780000000000</dc:source>.

    3 replies

    R
    Ruben Solér
    Inspiring
    March 7, 2025

    I've been getting a similar error:

     

    ERROR: OEBPS/content.opf(23,49): Undefined property: "pageBreakSource".

     

    The only way I've been able to fix it has been to uncheck the page navigation option on export from InDesign. It would be nice to use the ISBN from the physical book as the source, but quite often text will move in the InDesign document when we prepare the EPUB. I'd rather not use the feature unless I know it' accurate.

    L
    Laura Brady
    Inspiring
    March 7, 2025

    You need to update the version of EPUB Checker that you are using. This isn't an error and has very recently been fixed. 

    https://pagina.gmbh/startseite/leistungen/publishing-softwareloesungen/epub-checker/

      N
      noras12574007
      Participant
      March 7, 2025

      Thank you, Laura. I should have noted that I don't get the error myself (I use epubcheck 5.2.1). It's when our clients try to upload to a specific vendor that they get the error. I'll inform the vendor that they should update the checker they use. Again, many thanks.

      L
      Laura BradyCorrect answer
      Inspiring
      February 11, 2025

      You could simply add a page source. This can now be done at export by adding an ISBN to the EPUB export wizard, on the first panel of the export suite of options. The main issue here is that InDesign is exporting it with specific metadata that some vendors are rejecting. To fix it, add this to the OPF of your ebook: <dc:source>9780000000000</dc:source>.

      James Gifford—NitroPress
      James Gifford—NitroPress
      Legend
      February 10, 2025

      First, it's not too uncommon to have to tailor EPUB exports to each sales portal. Where a generic export might be possible, it doesn't always make the best of each platform/reader's features.

       

      The page navigation markers are, as you note, new, but with the 2024 (v19) version. You can turn them off by unchecking Page Navigation in the EPUB export menu. As far as I know, no reader or platform demands these (yet), so that same version should pass validation on all sales portals.

      L
      Laura Brady
      Inspiring
      February 11, 2025

      That is terrible advice. Why would you counsel people to hobble their ebooks like this? 

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