Policy
Always use custom logon background
This policy setting 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 always attempts to load a custom background instead of the Windows-branded logon background. If you disable or do not configure this policy setting, Windows uses the default Windows logon background or custom background.
873ef0b2e47f UseOEMBackground Registry
Copy registry mappings
HKLM\Software\Policies\Microsoft\Windows\System\UseOEMBackground (enabled) = 1
HKLM\Software\Policies\Microsoft\Windows\System\UseOEMBackground (disabled) = 0Policy notes
This policy setting 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 always attempts to load a custom background instead of the Windows-branded logon background. If you disable or do not configure this policy setting, Windows uses the default Windows logon background or custom background.