Always use custom logon background Ignores Windows Logon Background. This policy setting may be used to make Windows give preference to a custom logon background. If you enable this policy setting, the logon screen will always attempt to load a custom background instead of the Windows-branded logon background. If you disable or do not configure this policy setting, Windows will use the default Windows logon background or custom background.

[enable/disable]

(1) GPO: Computer ConfigurationAdministrative TemplatesSystemLogon!Always use custom logon background (2) REG: HKEY_LOCAL_MACHINESoftwarePoliciesMicrosoftWindowsSystem!UseOEMBackground