Apple Books rejected your Epub

Apple runs the strictest intake of any ebook store. Files are validated with Epubcheck on the way in, and a single error is enough to block the book, whether you deliver through Apple Books for Authors, a Pages export, or an aggregator like Draft2Digital.

Read the rejection, then reproduce it locally

Apple's rejection messages usually quote Epubcheck output, so the code and message you see are the same ones a local validation gives you. That is the workflow: validate on your own machine, fix until clean, deliver once. The checker runs the same schema rules in your browser, explains each finding in plain language with the source line, and repairs the mechanical problems in one click. Your manuscript stays on your machine the whole time.

Validate your Epub now

The errors that block Apple deliveries

PKG-006: broken mimetype packaging, the standard result of editing a book and re-zipping it. Fixed automatically by the checker.
RSC-005: any markup that violates the content rules. The message text after the code identifies the actual problem; the linked guide walks through the common ones.
RSC-016: an unclosed tag somewhere in a chapter. Fatal, and it makes every error after it unreliable, so fix this one first and re-check.
RSC-007: images or stylesheets referenced but not in the archive.
OPF-029: an image whose real format does not match what the manifest declares, often a swapped cover.

Aggregators are the same gate

Draft2Digital, PublishDrive, StreetLib and the rest all forward to Apple, so a file that fails Epubcheck bounces there too, sometimes days later and with less context. Validating before the first submission saves the round trip.

Zero errors is the bar, but warnings are worth a look too while you are in there. They flag the kind of sloppiness (mismatched image extensions, say) that tends to become a real problem one format conversion later.