Require user name and password on logon is disabled

In the user window, the checkbox "Require user name and password on logon" is disabled and cannot be checked.

But by using the registry, we can simulate checking this box, we need to set the registry key HKLM\Software\Microsoft\Windows NT\CurrentVersion\Winlogon\AutoAdminLogon from 0 to 1

ReactOS Version: Build 20200511-0.4.15-dev-208-g909f50a.GNU_8.4.0 / BOOTCD

The virtual machine hardware:

1. Windows 2003 ( 32-bit)
2. Microsoft Windows
3. 1GB of RAM
4. PIIX3 Chipset
5. PS/2 Mouse
6. 1 CPU only
7. Hardware virtualisation: Enable Nested Paging
8. Paravirtualization Interface: Default
9. Video Memory: 128MB
10. One monitor
11. Graphics Controller: VBoxVGA
12. Acceleration: Enable 3D Acceleration
13. IDE Controller PIIX3 Type, don't use Host I/O Cache
14. A CDROM drive and an HARD-DRIVE
15. Bridged Network Adapter
16. Com1: Raw File

Reproduction Method:

1. First, go to control panel
2. Open User window.
3. You will see that "Require user name and password on logon" is disabled.

Here is the proof: 

How to enable "Require user name and password on logon"

1. Open CMD
2. Type Regedit
3. Double click HKEY_LOCAL_MACHINE
4. Double click SOFTWARE
5. Double click Microsoft
6. Double click Windows NT
7. Double click CurrentVersion
8. Click Winlogon
9. Double click AutoAdminLogon
10. Set it to 0
11. And reboot the machine
12. You will see the Press CTRL-ALT-SUPPR to logon

Have a nice day.