Originally Posted by geekmaster
Twobob is correct. The screenshot shows a filename WITHOUT the "_ssh"] in the folder, which does not match the filename on his fastboot command line. That explains the error message. Also, it helps a LOT if you configure Windows to NOT hide file extensions.
Unhiding file extensions certainly helped. I flew through a good chunk of the instructions after that was cleared up. I got stuck again but I think I just figured it out. I'm almost there!
Update: I finished up. I now have a fully functioning Kindle. Thank you all so much for your help! This is a very kind community.