Thanks to Moab's comment and link I found the information here: http://www.addictivetips.com/windows-tips/switch-from-a-microsoft-account-to-a-local-account-in-windows-10/
So, here are the steps (sans pictures) to do this:
- Go to "Your email and accounts"
- Either "Windows menu button -> Settings -> Accounts -> Your email and accounts"
- or "Windows menu button -> {your username} -> Change account settings"
- Select "Sign in with a local account instead"
- Enter your current password and click "Next"
- Change the username (mandatory, unfortunately)
- Enter your new password and confirm it
- Enter a password hint (also mandatory, unfortunately. However, it does accept a single space:
as your hint)
- Click "Next"
- Click "Sign out and finish"
Once back at the login screen select your new username and type in your new password. Your files will be where you left them but now the path won't match your username as it did before as it will still include your old username.
You may find that some settings are different such as being prompted again: "Do you want to make {non-Edge browser} your default?"
Bonus information: To log out of your account manually, click the Windows menu button -> {your username} -> Sign out.
Bonus bonus information: To change your local username back to your original one:
Open "User Accounts" in Control Panel (I typed "account" into the Settings window's search or you can use one of the methods from the following link)
http://www.isunshare.com/windows-10/7-ways-to-open-control-panel-in-windows-10.html
- Click "Change your account name"
- Type your new account name and click "Change name"
- Log out (see Bonus information above) and your new old name will be applied!
Windows doesn't care that you've used that name previously.