Understand the pre-flight checklist

What you'll do: read the checklist at the top of the Export step and clear anything it flags before you publish.

What pre-flight checks

Pre-flight is a quick, automatic check that the essentials of a valid, sellable book are in place. Each item shows one of three icons:

• ✓ tick — all good.
• ! warning — a suggestion worth looking at, but you can still export.
• ✕ cross — something required is missing; fix it before exporting.

Typical items

• Title, Author, Language — required metadata. Add them on Setup.
• Cover image — required by most stores. See Add a cover image.

What to do

Work down the list and clear every cross. Warnings are your judgment call. Once the essentials pass, go ahead and generate your EPUB or make a print PDF.