Display administrator account on log on screen

I have a dimension 8400 with Windows XP home on it.

 

I am attempting to have all users but the administrator accout limited to user access.

 

I need to display the admin account on the log in screen.

 

I have edited the registry HKEY_LOCAL_MACHINE  SOFTWARE  MICROSOFT  WINDOWSNT  CURRENT VERSION  WINLOGON  SPECIALACCOUNTS  USERLIST  to have an administrator name with data set to 1.

 

The account will still no display.

 

This worked with my other computer with XP Pro on it.

 

What is the problem?