I have The Complete Works of Carl Jung in EPUB format, but every time I try to send it to my Kindle via the Kindle app on my phone or via the "Send to Kindle Website", Amazon's internal conversion process takes almost an hour and ends up failing.
The reason I want to send this to my Kindle device this way is simply to keep it in the cloud.
The EPUB is 49 MB. It can be opened without any problem on my computer and on the Kindle when I sideload it via USBC cable.
I've tried making sure the HTML is UTF-8 encoded (I know this measure is useless); I also tried converting the file from MOBI to EPUB; also converting the file from EPUB to KPF and then back to EPUB (both with Kindle Previewer and the Calibre plugin), but the result is always the same. When I send it to the Kindle via Send to Kindle, it fails.
When I run the "Quality Report" in the Kindle Previewer, I get a pop-up saying "13367 quality issues were found in this book", indicating that the file has the same number of non-indexed footnotes. However, the report says that this issues shouldn´t prevent the file from being used.
Does anyone have an idea why this particular file can't be uploaded to the cloud?