Martin,
I have the impossible PIN problem so now I am using a different computer. I may buy a new HD for the bricked computer.
Every large company I deal with sends me an email confirmation after we do anything. Why can't MSFT email every change in PIN or Password to its users? And why not force the change to take 1 week? That is, for a week, the user could still use the old method, but after a week MSFT sends them a second email with their new PIN and bricks their computer if they lose the email. You know, be kind.