The author openly admits to jailbreaking their iPhone. These kinds of users tend to install many types of "tweaks" on their computers, and I would bet that this is the cause of the update failure.
You would bet and loose. I did do a clean install from a Dell recovery USB image, that's part 2 of the article. Also, I don't "openly admit" to jailbreaking my iPhone. I nonchalantly mention this :)
The author also admits to downloading a fresh restore image from Dell, which I would assume would create a fresh install of Windows without any "tweaks," and then still experiencing the same issue.