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Participant
February 21, 2024
Question

Error in Epub - indesign I have received back from my team and don't understand

  • February 21, 2024
  • 5 replies
  • 3413 views

Hi,

I have an issue with a fixed layout epub, my team reported back to me this error when trying to upload it. This is a first time that it has popped up and I don't know what it means. Has anyone ever had this and how can I fix it? 

 

" PKG-026: Obfuscated resource must be a Font Core Media Type (was declared as "application/x-font-ttf" in "OEBPS/content.opf").META-INF/encryption.xml L5 META-INF/encryption.xml L23 "

 

screenshot here :

5 replies

Participant
April 2, 2025

Did you get a workable solution to this because a year later and I am having the same problem?!!!!

 

Thanks

James Gifford—NitroPress
Legend
April 2, 2025

Run your EPUB past the most current version of EPUBchecker — NOT any wrapped, app'ed or commercialized version. If it passes the latest version, the problem is not yours. But it's hard to do anything about sales/distribution portals that are still running older versions of validation.

 

The EPUB 'industry' being perpetually out of step with each other is one of its more persistent and aggravating problems.

Participant
April 3, 2025

Thanks James. I will give that a go. I have raised it with Ingramspark... no reply (meh!)

 

Inspiring
November 12, 2024

This is a known issue and is related to TTF fonts. When you export from InDesign they come out with "application/x-font-ttf" in the manifest. If you change that to "application/vnd.ms-opentype" your fonts will still work just fine and you won't have a validation error. 

Participant
January 24, 2025

I've just encountered this problem with a book I've tried to upload to IS for a client. How do I go about changing  the above when exporting from InDesign to EPUB?

Inspiring
January 24, 2025

It's not possible from InDesign. Fixing this requires you to go into the EPUB code to manually fix the font type. 

Participant
November 12, 2024

I had this problem when I tried to upload the ebook to IngramSpark.

 

Using Calibre, I converted the epub into an epub (yes, the same file format) and that fixed the problem.

James Gifford—NitroPress
Legend
November 12, 2024

This is an interesting approach, and of course in line with the routines for fixing corrupted InDesign and Word files. It depends, however, on the reliability of Calibre to write/rewrite code, not only for technical compliance but preserving anything outside standard, vanilla layout. I'd see it as more of a bandaid/hack than a proper approach, that of finding the actual cause of the fault and fixing it.

 

(I profess to be a bit baffled by the "e-book conversion" boffins. When format conversion isn't something verging on piracy, it seems unnecessary to me to convert the same book to read on different readers... but it is or was quite the active segment of the reader/collector/hacker area of the field.)

Participant
November 12, 2024

I actually think (in my case) the problem is IngramSpark's.

 

We have a professional ebook converter (and I used to convert ebooks in the day when they were written in code from scratch).

 

The ebook uploads fine on Amazon KDP, and various ebook readers (like Kindle, iBooks, Calbre's own reader) have no problem withit. (iBook's is actually a good test of coding -- if there's a problem, it'll complain as you're going through the book on the page with the issue.) But IngramSpark flagged it.

 

In the past, I've found IngramSpark flag things that these other platforms don't. Also, often it flags things that are redundant, e.g. a tag that's not closed in the code, even though that has no bearing on how the ebook functions.

 

Interestingly, when I went into Calbre's ebook editor and used its automated fix, it broke more things as far as IngramSpark were concerned, e.g. whereas IngramSpark flagged three things previously, now it was flagging twelve.

 

But using Calibre's converter (converting it from epub to epub) fixed it for uploading on IngramSpark.

 

I'm guessing the conversion is just embedding the font in a way that's satisfying IngramSpark's internal evaluation.

 

 

James Gifford—NitroPress
Legend
February 21, 2024

You have a bad font — bad for EPUB embedding/encryption. There are few solutions except replacing it with a font that is compatible/licensed for e-book export.

Inspiring
November 12, 2024

It is not a bad font; it's related to the media type and is easily fixed. 

Participating Frequently
May 22, 2025

Hello DS. Can you email it to me? I will record a short video of how to fix it using open-source software so you are armed for this problem in the future. 

 

 

<Personal info removed by MOD>


Hi Laura, 
I tried your email address, got this:

Your message wasn't delivered to --------------- because the domain bradytypesettting dot com 
I'm at ---------------------
I really appreciate your help - I can be kind of a klutz with 'digital communication' ... 
DS

 

 

 

<Personal info removed by MOD>