My customer has 50,000 or so retail kiosks that they are rebuilding from Windows 7 to Windows 10. An interesting problem popped up with these. When we build a Windows 10 machine in the Windows 7 OU, the desktop background doesn't appear. Instead, we get a black screen.
A bunch of troubleshooting later, we discovered that this occurs because Windows 10 can't write to the Hkey_Current_User\Control panel\Desktop section of the registry. There is a deny permissions entry that forbids it.
How on earth would this setting get there?
Skip a bunch of troubleshooting, and ... we set it, unintentionally, via GPO.
This comes from a User side Group Policy setting:
Administrative Templates >> Control Panel >> Personalization >> "Prevent changing desktop background"
This insidious setting creates a deny permissions entry in the registry. Even worse, this is a tattooed setting. Removing the GPO does NOT remove it.
Removing the GPO setting caused all of our new machine builds to work properly, but unfortunately does not fix the tattooed broken systems.
To fix the in-state systems we either rebuild them (For us, they are kiosks and this is easy.) or ...
1. Remove the deny permission entry with a scheduled task script.
2. Change the desktop background to a new background to force it to refresh.