Able to change Login Wallpaper, but what about Lock screen wallpaper?

[cgolebio]

It was requested that all corporate computers receive a custom wallpaper at the lock screen. While this is easy for our Windows computers, this has proved a bit difficult for our Mac systems.

I can easily change the wallpaper for the login window at FileVault or if you logout and are at the window by replacing com.apple.desktop.admin.png in /Library/Caches/. However, when the computer locks after coming out of screensaver or otherwise it is back to the blurry overlay.

Has anyone been able to get around this?

I know I posted in an older thread but didn't see any response. Figured I'd create a new discussion topic for this. I appreciate the help.

[scottb]

I just built a new (older model) 13" MBP. Will test with macOS sierra in a bit.

[scottb]

So, I see that it is working except when I set the Security pref pane to logout after x minutes.
If I manually logout, it's fine.
If I go to Login Window from FUS menu, it's fine.
Oh so much fun!
One thing to make sure of is the name the file with the .png name. Don't just save it as a .png.
As for this conundrum...no clue.

*Edit. just a thought. Maybe it's some sense of Apple "security" to make the device "generic" if it's pilfered? Dunno. Not sure if I hope for a glitch/bug or an Apple bright idea...

[cgolebio]

Thanks, So I can get it to work with login/logout as well and with FileVault login window. However, lock screen after computer comes back from sleep and lock screen after screen saver is now what I am after to complete the mission. Where is that transparent overlay coming from and is it possible to actually change? I am sure if it is an image file that it is in a SIP protected location.

Chris

[scottb]

@cgolebio - that's a good question. Now, I don't recall if this was happening in older iterations of macOS, so I don't know if it's specific to Sierra or not. Hoping someone smarterer than me has some clues...