EPUB FixerKDP upload error scanner

EPUB error guide

Kindle Previewer EPUB errors

How to turn Kindle Previewer EPUB errors into a structured repairability report before another KDP upload.

Error text

Kindle Previewer reports structural EPUB validation errors.

When you usually see it

The EPUB opens enough to preview, but Kindle Previewer reports package, metadata, TOC, link, or resource errors.

Plain English

What it means inside the EPUB.

Previewer errors usually mean the EPUB package is not structured the way Kindle expects, even if the book appears readable in another app.

Typical causes include missing nav or NCX wiring, OPF metadata conflicts, broken resources, invalid anchors, and incorrect ZIP packaging.

User checklist

What to inspect before another upload.

These checks keep the repair decision tied to the EPUB package instead of guessing from a generic error code.

Standards context

Why this error matters to validators.

KDP eBook file formats

KDP supports EPUB files that meet Kindle Publishing Guidelines and recommends checking the file with Kindle Previewer before upload.

EPUBCheck

EPUBCheck evaluates EPUB 2 and EPUB 3 publications against official EPUB specifications and reports structure, package, markup, and reference problems.

Repairability

Can EPUB Fixer repair it?

Safe repair condition

EPUB Fixer groups these errors into repairable, manual, and out-of-scope buckets so you know whether another export, a targeted structure repair, or manual formatting help is needed.

When it stops at diagnosis

It does not solve KDP account, tax, pricing, category, review, cover design, or book formatting issues.

Before / after example

Before: Previewer shows several raw validation messages. After: the report lists affected files and separates deterministic fixes from manual work.

Next step

Scan the actual file before editing by hand.

The same error code can come from different files and different causes. Uploading the EPUB lets the report show the affected path and whether the fix is deterministic.

Upload EPUB to scan

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