Knowledge · Rule
Missing or mismatched NCX / nav document
Navigation · E-NCX
Definition
Kindle needs a table-of-contents navigation file (NCX for EPUB 2, nav doc for EPUB 3). Yours is missing or doesn't match your chapter headings.
Why
- toc.ncx or EPUB 3 nav document was never added to the package.
- Manifest does not declare the NCX/nav item, or the spine toc attribute points elsewhere.
- Nav entries were built from an old outline and no longer match chapter files or heading ids.
- EPUB 3 package missing <nav epub:type="toc"> while only an incomplete NCX remains.
Impact
May block submission on KDP when this rule fails.
Platforms
| Platform | Result |
|---|---|
| KDP | May reject |
| Apple Books | May reject |
| Google Play | May reject |
| Kobo | Warning |
References
- EPUB 3 Navigation Document
- Amazon Kindle Publishing Guidelines
- Cermify Rule Set kdp-epub-2026-07
Last updated · 2026-08-03
Why we believe
Provenance is loaded from RID (same source as Rule Radar) — not a second copy.