Create a Group Policy Object
To create a Group Policy object (GPO) to change the administrator and guest account names:

Start the Active Directory Users and Computers snap-in. To do so, click Start, point to All Programs, point to Administrative Tools, and then click Active Directory Users and Computers.
In the console tree, right-click the domain or the organizational unit where you want to create the group policy, and then click Properties.
Click the Group Policy tab, and then click New.
Type the name that you want to use for this policy. For example, type Rename Administrator and Guest accounts, and then press ENTER.
Click Close.
Rename the Administrator and Guest Accounts

Start the Active Directory Users and Computers snap-in.
In the console tree, right-click your domain or the organizational unit that contains the Group Policy that you want, and then click Properties.
Click the Group Policy tab, click the Group Policy object that you want, and then click Edit. For example, click the Rename Administrator and Guest accounts Group Policy object, and then click Edit.
Expand Computer Configuration, expand Windows Settings, expand Security Settings, expand Local Policies, and then click Security Options.
In the right pane, double-click Accounts: Rename administrator account.
Click to select the Define this policy setting check box, and then type the new name that you want to use for the administrator account.
Click OK.
Double-click Accounts: Rename guest account.
Click to select the Define this policy setting check box, and