Hello
Thank you for your question and reaching out. I can understand you are having query\issues related to Lock screen GPO not applied.
Please verify below GPO settings and registr is set.
- “Computer Configuration\Administrative Templates\Control Panel\Personalization\Force a specific default lock screen and logon image” is enabled.
- "Computer Configuration\Administrative Templates\Control Panel\Personalization\Prevent changing lock screen and logon image" is enabled
- HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\System\DisableLogonBackgroundImage is set to 1.
- On member server run gpresult /h C:\temp\gpresult.html to verify GPO settings have been applied .
Reference :
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