There are many ways to change the name of the Administrator account, but with the following method is considered the simplest and easiest to do. Let’s join ElectrodealPro to change the name of the Administrator account.
Rename the Administrator account on Windows
Step 1: From the Desktop, right-click My Computer and click Manage
Step 2: Click to select System Tools -> Local Users and Groups -> Users. In the right pane, right-click your account Administrator then choose Rename
Step 3: Here you can change this account name.
Above we have instructed you how to change the name of the Administrator account on windows to ensure the security of the system, with this presentation you can easily and quickly do it. Also you can refer to how Enable Administrator account in Win 8 here