AZW3 Won’t Open on Colorsoft – Need Help

[avas]

Hi everyone,

I’m trying to load AZW3 eBooks (converted from EPUB, not from Amazon) onto my Colorsoft, but I keep getting error messages. Sometimes I can read a few pages, but most of the time they won’t open at all.

I’ve tried:

- Using Calibre via USB
- Send to Kindle (still fails to open)

These same AZW3 books work fine on my 2021 Paperwhite.

Has anyone found a reliable way to get non-Amazon AZW3 eBooks working on Colorsoft? Any advice would be greatly appreciated!

[Quoth]

Reboot the colorsoft, or factory reset.

Surely STK is epub -> KFX for a colorsoft?

Make sure that they are azw3 / KF8 and not old mobi or dual mobi, which will work on most PW, but might not on a Colorsoft.

Has it big images?

[avas]

Originally Posted by Quoth

Reboot the colorsoft, or factory reset.

Surely STK is epub -> KFX for a colorsoft?

Make sure that they are azw3 / KF8 and not old mobi or dual mobi, which will work on most PW, but might not on a Colorsoft.

Has it big images?

Sure, the file is in EPUB format when I upload it to STK

I’ve confirmed all the converted files are AZW3 (not old MOBI).
I already tried rebooting and even factory resetting the device, but still no luck.

Interestingly, for manga in AZW3 format, I can read them without issue. But once I import an AZW3 book with only text, the error message appears — and after that, I also can’t open the manga anymore.

[Sirtel]

Does it read Amazon purchases directly downloaded from Amazon? If not, then something is clearly wrong with your Colorsoft.

[tomsem]

There is nothing wrong with the Colorsoft, it will have to do with the specific ePub file in question. I suspect it is a fixed layout ePub; it's also possible that it has other problems, e.g. doesn't pass epubcheck.

A good test is to open with Kindle Previewer. If it barfs, then it will emit an error report, maybe you can fix and try converting again.

But if it is fixed layout ePub (comic book or some such), STK will not convert it properly: it does not support fixed layout ePub and will munge it into reflow able AZW3, and poorly at that. Calibre does not support fixed layout ePub, and will not convert it to usable fixed layout AZW3.

It does not seem like rocket science to do such a conversion, but I've been unable to discover a tool that does it.

I would look at source code for KindleUnpack; it will do AZW3 fixed layout to fixed layout ePub, maybe someone could reverse the workflow to do the reverse operation.

If it consists only of page images (without positioned text & embedded fonts) then you could extract the images (there's a function in calibre-edit to do this) and then build AZW3 with Kindle Comic Converter, or build KFX with Kindle Create and KFX output plugin. Of course either of those needs to be side loaded.

[Sirtel]

Originally Posted by tomsem

There is nothing wrong with the Colorsoft, it will have to do with the specific ePub file in question. I suspect it is a fixed layout ePub; it's also possible that it has other problems, e.g. doesn't pass epubcheck.

A good test is to open with Kindle Previewer. If it barfs, then it will emit an error report, maybe you can fix and try converting again.

But if it is fixed layout ePub (comic book or some such), STK will not convert it properly: it does not support fixed layout ePub and will munge it into reflow able AZW3, and poorly at that. Calibre does not support fixed layout ePub, and will not convert it to usable fixed layout AZW3.

It does not seem like rocket science to do such a conversion, but I've been unable to discover a tool that does it.

I would look at source code for KindleUnpack; it will do AZW3 fixed layout to fixed layout ePub, maybe someone could reverse the workflow to do the reverse operation.

If it consists only of page images (without positioned text & embedded fonts) then you could extract the images (there's a function in calibre-edit to do this) and then build AZW3 with Kindle Comic Converter, or build KFX with Kindle Create and KFX output plugin. Of course either of those needs to be side loaded.

There are more than one book, they're text-based (not images) and work perfectly on the OP's other Kindle. So it does seem to be an issue with their Colorsoft.

[tomsem]

Originally Posted by Sirtel

There are more than one book, they're text-based (not images) and work perfectly on the OP's other Kindle. So it does seem to be an issue with their Colorsoft.

I missed that, thanks.

Still it seems (post #3) STK is converting it to AZW3, when normally it would be converted to KFX. The only cases I've seen this happen are when conversion to KFX fails, which points to issue with source file. That's why I suggested feeding it to Kindle Previewer to see what happens (or use KFX output plugin to attempt conversion to KFX, which uses Kindle Previewer).

And of course it would be informative to try the AZW3 on some other Colorsoft, or even some other 2024 Kindle. Is this particular CS defective? or have they somehow botched up AZW3 support in newer models?