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PKG-010Critical Ingestion Error

The file name "resource" contains spaces, which may create interope...

The file name "resource" contains spaces, which may create interoperability issues with older reading systems.

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What This Error Means in Plain English

EPUBCheck detected The file name "resource" contains spaces, which may create interoperability issues with older reading systems.. Digital reading systems and bookstores require standard conformance to ensure compatibility across all reading apps.

Why Retailers & EAA Regulations Block This File

Automated book distributors (Apple Books, Amazon KDP, Kobo, and IngramSpark) run strict EPUBCheck validation on ingest and reject non-compliant files.

Technical Specification: W3C EPUBCheck rule PKG-010: The file name "resource" contains spaces, which may create interoperability issues with older reading systems.

Manual Fix Instructions (for Sigil / Calibre)

  1. Locate the file and line flagged under rule PKG-010 in your EPUB editor (Sigil or Calibre).
  2. Apply the required syntax correction matching the PKG-010 specification.
  3. Re-pack and validate with PreFlight EPUB to confirm zero residual errors.