This policy setting prevents users from changing their Windows password on demand. If you enable this policy setting, the ...

This policy setting prevents users from changing their Windows password on demand.

If you enable this policy setting,  the 'Change Password' button on the Windows Security dialog box will not appear when you press Ctrl+Alt+Del.

However, users are still able to change their password when prompted by the system. The system prompts users for a new password when an administrator requires a new password or their password is expiring.