How to Change the Account Name on a Mac
- 1). Click the Apple icon in the top left of the screen, and then click "System Preferences."
- 2). Click "Accounts," which is located under the "System" section of the "System Preferences" window.
- 3). Click the Lock icon in the lower left corner of the screen if it is locked. Enter your password so that changes to your settings can be made.
- 4). Enable the Root User account by clicking "Login Options" below the account names on the left side of the "Accounts" window, and then click "Edit" or "Join," whichever is displayed. Click "Open Directory Utility," and then enter your user name and password if prompted. Click "Edit" at the top of the screen, and then choose "Enable Root User." Enter a password to use with the Root User account, and then click "OK."
- 5). Click the Apple logo at the top of the screen, and then click "Log Out."
- 6). Click "Other" at the login screen, enter "Root" as the user name and enter the password set as the Root User password into the password field. Click "OK" to log in to the Root User account.
- 7). Open a new "Finder" window, and then click on your main hard drive. Open the "Users" folder on the right side of the window.
- 8). Select the folder with the name of the user that you would like to change, and then click on the name once again to change it. Enter the new name that you would like to appear on the folder. Be sure to use all lowercase letters and no spaces.
- 9). Open the "Accounts" window once again from the "System Preferences" screen.
- 10
Create a new user account by clicking on the "+" box below the user account list. Be sure to name the new user the same name given to the folder that was renamed. - 11
Click "OK" when alerted that a folder already exists with the newly created user name. - 12
Click the Apple logo and "Log Out." Log in to the newly created user name by clicking on its icon and entering the password that was set when the account was created. - 13
Open the "Accounts" window once again from "System Preferences." - 14
Delete the old user account by selecting it and clicking the "-" button below the account list. - 15
Disable the Root Account using the same method used to enable it.
Source...