Troubleshooting
Uploaded the wrong ebook file type (a Word doc where a real EPUB was needed, or vice versa)
How you'd notice this
An ebook upload fails, gets flagged as invalid, or a platform simply won't accept the file you selected, and the underlying cause is that this specific platform's ebook slot expected a different kind of file than the one you had. EPUB (a reflowable, screen-adjusting ebook file) and a plain .docx Word document are not interchangeable, and different platforms want different things here.
Why it happens
The platforms genuinely don't all work the same way. KDP and Draft2Digital both accept a plain, well-formatted Word document and run it through their own automatic conversion into a proper ebook file, you never have to build an EPUB yourself on either of those. IngramSpark works differently: it expects you to hand it an already-built, valid EPUB file (EPUB 2 or 3) directly, it does not auto-convert a Word document for you. Uploading a Word file where IngramSpark wants an EPUB, or assuming you need to hand-build an EPUB before you can use KDP or D2D at all, are both common first-time mix-ups because the platforms genuinely differ here.
How to fix it
- Check which platform you're on before uploading. KDP: upload a clean .docx directly (it auto-converts), or upload a real .epub if you already built one. Draft2Digital: same, a plain manuscript file (.doc, .docx, .rtf, .odt, .txt) is enough, D2D converts it, or upload your own .epub if you have one. IngramSpark: a genuine .epub file is required, a plain Word document will not work here.
- If you need a real EPUB and don't have one: Atticus has a built-in Export EPUB button (Formatting tab, under the live Previewer). Adobe InDesign has a real EPUB export at File → Export → EPUB (Reflowable). Microsoft Word has no built-in EPUB export, use the free Kindle Create app or Calibre (free, File → Convert Books) instead. Google Docs has no EPUB export at all, download the Doc as .docx first, then run that through Calibre.
- If you only have a print-ready PDF and need an EPUB for IngramSpark specifically, IngramSpark's own paid EPUB Conversion service can convert it for roughly $0.60 per page, usually taking about 15 business days.