I'm trying to modify the content of an already published book. I had a company create the file for me so all I have is the Kindle file. I went to the help section on this topic and it said:
To download your book content file:
1. From the 'Bookshelf,' select the 'Actions' drop-down menu next to the book you wish to modify.
2. Select 'Edit book details' in the menu.
3. Scroll down to the Book Content section and click 'Preview Book.'
4. Click 'Download HTML.'
5. Choose a location on your hard drive to which to save the ZIP file, then click 'Save.'
Unfortunately, I do not see step 4. Can anyone help please?
You can't download the HTML source when you've uploaded a mobi file since these files are not converted through Amazon's systems, aside from some modifications to metadata.
When a mobi file is made with official Amazon tools the source used to compile it is embedded as a zip file in that mobi, so you may be able to use something like 7zip to open the file and extract the source. If they used something like Calibre (which they shouldn't, but many low quality shops do) or have stripped the source this obviously wouldn't be possible.
Another option would be to see if the company that did the conversion for you will provide the source. I'll generally hand over the source to books that I format upon request, but I somehow doubt this is a common practice.
I'm sure you could get them to do the update for you, but they would almost definitely charge for the work.