To Show the Main Administrator on the Welcome Screen, open the Registry Editor (Start, Run, regedit) and locate the Key
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\SpecialAccounts\UserList\Administrator
and give it the value 1.
To Remove the Administrator from the Welcome Screen, just delete the value.
Note : If Administrator does not appear in the UserList Key, just add "Administrator" as a DWORD Value.
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\SpecialAccounts\UserList\Administrator
and give it the value 1.
To Remove the Administrator from the Welcome Screen, just delete the value.
Note : If Administrator does not appear in the UserList Key, just add "Administrator" as a DWORD Value.