I got an error message about my epub file.

These errors apply to authors who uploaded an epub to Pronoun. If you uploaded a Word document, please see our Conversion troubleshooting & FAQ for more information.

When you upload an epub to Pronoun, we run checks to make sure your book won’t be rejected by retailers. Here are some of the errors that may come up:


Some retailers won’t sell books that mention or link to their competitors. Please make sure your book doesn’t contain:

  • Links to retailers like Amazon or Barnes & Noble
  • References to specific retailers (say “leave a review on your preferred store” instead of “leave a review on Amazon”)
  • Images that include specific retailer logos or names

We recommend linking to your personal website, social media (e.g., Facebook, Twitter, Goodreads), Pronoun book page, or Pronoun author page instead.

Note that your book can contain retailer links if it’s only being distributed to that retailer. For example, a book only going to Kobo can include Kobo links.


“Your epub does not contain a cover image.”

Retailers require ebooks to contain a cover image—otherwise, your book will show up in readers’ libraries with a placeholder cover. 

To resolve this issue, please add a cover image to your ebook file. Epub creation programs generally have an “Add cover” option somewhere in the tools menu. You can also add a cover image to your epub using a program like Calibre.

A good way to tell if you’ve successfully added the cover is to open your book using an ereader, like the iBooks or Kindle app. If you see your cover in the digital library, rather than a placeholder image, you’re good to go. 

The epub on the left includes a cover image, the epub on the right does not.

Additionally, please also make sure your cover image is the first page inside your book. Here’s how it might look:

The first page of this book is the cover image, followed by the title page.


“Epub contains images larger than 4 million total px.”

Apple has a 4 million pixel maximum limit for images, and this error means that your epub contains at least one image that’s too large for iBooks to accept. (Frequently, it’s the cover.) You can resolve this issue by using smaller image files in your book.

Pixel size refers to the width multiplied by the height of your image. For example, our recommended cover size of 1,600 by 2,400 pixels is 3.84 million pixels. Pixel size is unrelated to the file size (measured in KB or MB) of your cover.

Additonally, please note that this error is unrelated to the cover image you upload separately on Pronoun. (We don’t insert that image into your provided ebook files.) The too-large image is located inside your epub file.


“This is a proof copy created by Pronoun...”

This error means that the epub you uploaded is a Pronoun author proof. (The epub was created by converting a Word document on Pronoun.)

Pronoun proof copies aren’t designed to be published: they contain Proof for Review and Improve Your Formatting pages that are intended for the author only.

Please upload your original docx or submit final epub and/or mobi files.


“Your ebook file cannot contain audio or video content.”

Pronoun doesn’t support audio- or video-enhanced ebooks at this time.


My error isn’t listed here.

Some additional errors can be seen by using this online validator. However, since retailers use a different set of checks, your epub may pass the validator but still fail retailer checks.

You may need to work with your ebook creator to fix remaining issues, or try using our docx ebook conversion instead. If you have questions, email publish@pronoun.com.