Error message in upload of epub file

Hi, I’m uploading my epub files to my distributor and I keep getting this error message when I upload. What does this mean and how do I fix it?

(RSC-005): /EPUB/toc.xhtml: Error while parsing file: Anchors within nav elements must contain text

When I googled it, I found some people had a table of contents that was glitchy. I am using the Pressbooks TOC option but can’t see how to change anything in it, since it is auto-formatted.


I tried turning off the two level TOC option and that did not make any difference. I am using the Adunis layout. This is for two different book projects being exported in PDF and EPUB, to Ingram. Time sensitive!

The error message says that anchor elements (i.e. links) within nav elements must have text. This indicates to me that you have front/back matter, or a part or chapter that has an empty title. Make sure you don’t have any blank/empty titles and make a new export. You should be good.

Yes I had deliberately left some blank in the front matter - it has not been a problem in the past. Is that a new thing? I will change it on my end. Thank you so much, I’m relieved it is only this.

I changed the front matter headings and deleted one section. This meant I needed to add a page at the end to make up an even number page count. I did this by adding blank spaces to force a new page to be added. But, when I uploaded my file to my distributor, I got another error message, this time “Invalid epub file.” Please help! Did this happen because I forced a new page with blank spaces, and is there a better way to add a blank page with no heading? I’m fine with the page number being printed on it. Thanks!

@ASEIArts if you’re not able to upload the file to your distributor, you will need to check with the distributor about why they considered the file invalid. We have no way of knowing what triggered their error, nor whether it’s something wrong on their side, your side, or with the Pressbooks platform. All Pressbooks can do is help you to produce valid EPUB 3.2 files, and you’ll know it’s valid if you don’t get any errors/warnings from EPUBCheck after producing the EPUB file. What your distributor does/checks after that is out of our hands.

How do I add a blank page?

  1. added pages in Adobe Acrobat, no problem.
  2. still getting error message and found this on my distributor’s page: “Format: Must be EPUB 3.0.0 compliant. We cannot accept enhanced EPUB 3 files at this time.” You mentioned that Pressbooks produces 3.2 files. Can I backsave to 3.0.0? I did use a 3rd party checker to verify the integrity of the Pressbooks epub file and no errors were found, so this might be it.


@ASEIArts sounds like something to take up with your distributor. Who is it and what kind of support do they provide for uploading/evaluating the file validation?

It is Ingram and it is all automated. They direct users to the 3rd party epub file verifier Pagina, which I used, and which said the file is fine. Is there a way to backsave in Pressbooks to an older version? Thanks!

For reference, EPUB 3.2 is a very minor update to EPUB 3.0.0. See EPUB 3.2 Changes. We don’t support EPUB 3.0.0 exports, because it’s not a current standard. There really ought to be no major compatibility issues between the two formats. I do think this is a problem with your distributor, not Pressbooks’ export process.

So the question is, is it possible to create a version 3.0 epub file on Pressbooks, or anywhere else?

I don’t think converting an EPUB 3.2 file to EPUB 3.0 is a thing. Pressbooks made an EPUB 3 file for you – it just happens to conform with the EPUB 3.2 specification instead of the earlier spec. In my opinion, I think the better question is why Ingram is rejecting a valid EPUB file produced with Pressbooks (the file passed EPUBCheck and apprently Pagina’s verifier as well). Only they can answer that. If it turns out the answer is because of something Pressbooks is doing wrong, let us know and we’ll try to fix it in our export routine.