Solution for changing Big Sur login wallpaper to custom.

One item that helped me here was distinguishing what was the proper "Cache" - I found at least two locations on my Mac mini and three on my MacBook.

1)Finder/Go/Library/Caches. Didn't work here

2)MacHD/Library/Caches. I had to create the Desktop Pictures folder, and then the UUID folder. I put the"lock screen.png" in the UUID folder. After shut down, its working.

Hope this helps.

Hi James,

Are you looking in the right directory? It's the library folder of your hard drive, not your user folder.

You'll have to create the Desktop Pictures folder if it doesn't exist in Macintosh HD > Library > Caches. On my machine, I had to create the folder and then create the UUID folder with in it.

Once the folders are created you can go to System Preferences > Desktop & Screensaver and change the desktop to sometime different and then change it back. This will automatically create the file lockscreen.png.

Reboot your Mac and you should be good to go.

Hope this helps.

Soren Person said....Hi James,

Are you looking in the right directory? It's the library folder of your hard drive, not your user folder.

You'll have to create the Desktop Pictures folder if it doesn't exist in Macintosh HD > Library > Caches. On my machine, I had to create the folder and then create the UUID folder with in it.

Once the folders are created you can go to System Preferences > Desktop & Screensaver and change the desktop to sometime different and then change it back. This will automatically create the file lockscreen.png.

Reboot your Mac and you should be good to go.

Hope this helps.

There are other "cache" folders on my system, it's important to get the right one: Macintosh HD > Library > Caches. I also found that after an update, my computer reverted to the brilliantly ugly default. I rebooted with CMD-R*, went to disk utility and ran repair on both drives - Macintosh HD and Macintosh HD - Data before restarting, and it came back perfectly. There are probably better ways to do this.

(*Probably could have skipped the CMD-R but I'm also trying to get rid of a stuck Catalina install file on my system.)

Only 1 user account and Guest user account is off, yes.

FileVault is off, yes

But your 3rd question made me get to the temporary solution: When I changed the 'Login Options' to 'Display login window as: List of users' (instead of 'Name and password' as I had it), it gave me my chosen 'Desktop Background' on the login screen after a restart and/or new start.

This is obviously just a workaround and I have amended my bug report to Apple, as you shouldn't need to compromise security (FileVault and/or login windows).

I took the approach of visiting the Users & Groups Preferences panel, and altering the Login Options to Display login window as: ⦿ List of Users. A logout or log-in now shows my chosen Desktop wallpaper with my avatar above my name and password window. Gone is the ghastly bright Apple genuine migraine wallpaper.

The avatar window does not support transparency, but it might get a dark background shortly.

As VikingOSX said, change to 'list of users' rather than trying to change the Big Sur boot up image.

My system has never had a different 'log in' and desktop. Whenever I've right clicked on an image and selected 'set desktop wallpaper', it's always changed both.

However, the boot up one has always been whatever Apple set it to when changing the OS.

If your log in options are changed to 'list of users' as stated, the boot up image will be whatever your wallpaper is.

My guest user is always turned off, so if you have this on, you might need to turn it off—I'm not sure.

This method 100% works. Just have to make sure FileVault is off and the permissions have been set as detailed. When you go back to look in the folder it will take macOS a moment to generate the file but it creates itself rest assured.

Welcome, bmwapple, to Apple Support Communities!

If you have followed all the instructions, provided by applewarm, «to the letter», as you say, does that mean that you have only a single user on your system, including no Guest user?

Unfortunately, there was one thing that applewarm missed: making sure the “Display login window as:” is set to “List of users”, and not “Name and password”.

What this all does—on systems that are recognized, by macOS, as Single-User systems—is cause the Login Window to be skipped, skipping into the system’s Single-User’s Lock Screen (showing the lockscreen.png image for that user).

Unfortunately, none of this helps Multi-User systems, since they will always display the Login Window, that always shows the Big Sur Graphic image (the brightly colored, artists impression of Big Sur [perhaps at sunset]).

ted2019 wrote:

i tried following it but I did not need to change that image in that dir as it was already changed. My iMac has 2 users so it does not work from what you’re saying if you have multiple users. I will try it on my Mac book which is a single user over the weekend.

Yes. At this time, what we are able to change is only the Lock Screen background, and allowing the Login Window to be skipped, in the case of a Single-User system.

On Multi-User systems, or systems where the Login Window is set to use “Name and password”, the Login Window is never skipped.

All would be good, however, if we had the ability to change the background of the Login Window!

Unfortunately, none of us have figured out the “secret sauce” to make that change, yet, nor has Apple provided us with any tools for making that change, yet.

The best any and all of us can do, at this time, along such lines, is to provide Apple our Feedback, directly: Product Feedback - Apple.

I've been a long time Mac user as well, since the early 90s, MacOS 7.5 days so understand your point about being loyal.

Apple has changed, back then there was no iPhone or iPod, or app store which made then popular. It's amazing how they can push out updates to software and hardware like they do year after year and keep things running smoothly as possible.

They could address the login screen issue in a future software update though or you could submit feedback via product feedback.

I followed the instructions and it worked for me. I don't use File Fault so that's not an issue nor multiple users but would like the ability for it to work under the guest user if it's enabled.

You could check out OnyX when it's released for Big Sur and see if it allows you to change the login screen if you want to keep File Vault enabled and use your machine with multiple users.

I think what happened was the Desktop Pictures folder in Macintosh HD > Library > Caches > somehow over the beta period disappeared which caused the pictures to not sync to the login screen. This is just my theory.

If you don't want to follows the steps to change the login screen background that's on you. Just trying to help is all.

Please format your posts so they are easier to read rather then packing it into one block of text.

They did. System Preferences, Desktop & Screen Saver, Desktop

From there select Desktop Pictures if you want to use Apples OR photos to use your own

The Login Screen will automatically follow this setting ! It just doesn’t tell you that !

Hi Nelisniels1982,

Do you have a lockscreen.png file in the UDID folder?

If not, go to System Preferences > Desktop & Screensaver and select a different desktop background in order for the file to be created and then you can change it back to the Big Sur landscape and restart your Mac. It should work after this.

As long as Guest user and FileVault are off your login screen background will sync with your desktop background.

Hope this helps.

brianofTX,

I'm glad it works for you when FileVault is disabled. I have it working on my own Mac.

Yes FileVault needs to be off for the login screen to sync with your desktop picture.

Apple engineers/ the mac product management team do not read these forms as they are community based so your best bet is to submit a feedback request and hopefully it will get a address in a future update for Big Sur.

I feel it could be an artists representation of Big Sur or the waves at Big Sur. If you don't like the colorful background, the best thing to do is to keep FileVault off and use the this solution until Apple releases a fix.

I hope this helps.

StephCape wrote:

…

But your 3rd question made me get to the temporary solution: When I changed the 'Login Options' to 'Display login window as: List of users' (instead of 'Name and password' as I had it), it gave me my chosen 'Desktop Background' on the login screen after a restart and/or new start.

…

I hadn’t actually thought of that setting!

That’s something that should be added to the steps of the workaround presented as the core of this Discussion!