Do not display last user name in logon screen
Computer Configuration\Windows Settings\Security Settings\Local Policies\Security Options
Determines whether the name of the last user to logon to the computer is displayed in the Windows logon screen
If this policy is enabled, the name of the last user to successfully logon is not displayed in the Log On to Windows dialog box.
If this policy is disabled, the name of the last user to logon is displayed.
This policy is defined by default in Local Computer Policy, where it is disabled by default.