My husband bought me a book on his MAC and I am trying to download it on my Windows 64bit. Don't ask. So, I have Calibre from forever ago (back when I was in grad school) and I updated it to 3.37. Now I am greeted with the Kindle failed to convert message.

We didn't have that when I was in grad school. I use Kindle for PC (1.23.1). I cannot for the life of me figure out how to bypass this error. I have inserted every command prompt I can find you have written and suggested. I know you know a fix. Help a sister out? Thank you in advance for any assistance.