How do I change permission for the System/Library/DesktopPictures folder. I am still getting the "The operation can’t be completed because you don’t have the necessary permission." message.
[Edited by Moderator]
MacBook Pro 13″, macOS 12.3
Flycast47 wrote:
Freeing up drive space is not the objective, changing the hideous Lock Screen background is.
as already mentioned, the lock screen and the login screen are two different things. if you do indeed mean the login screen:
if you are the sole user (not even a guest account) AND file vault is turned off you can go to System Preferences > Users & Groups > Login Options and set "Display login window as" to "List of users". then your login screen matches your desktop background.
if you are using file vault or have multiple users, the above will not work. if that's your situation, you will need to wait for apple to address this. it may be worth your time to send feedback directly to apple. Feedback - macOS - Apple.
Flycast47 wrote:
Freeing up drive space is not the objective, changing the hideous Lock Screen background is.
as already mentioned, the lock screen and the login screen are two different things. if you do indeed mean the login screen:
if you are the sole user (not even a guest account) AND file vault is turned off you can go to System Preferences > Users & Groups > Login Options and set "Display login window as" to "List of users". then your login screen matches your desktop background.
if you are using file vault or have multiple users, the above will not work. if that's your situation, you will need to wait for apple to address this. it may be worth your time to send feedback directly to apple. Feedback - macOS - Apple.
I believe they are in the sealed system volume and cannot be deleted.
It may be possible if you boot into Recovery mode and use Terminal ... but then you would be messing around with the system volume and that's a risky proposition. And ... even if you delete the images they are likely to reappear next time you do a macOS update or upgrade.
If freeing up drive space is your goal, these images only take up 1-2GB and I'd suggest there are bigger fish to go after.
You cannot alter anything in the System folder. It's read only and there's no way for you to change that. Not in Terminal or any other method.
If you want to put your own photos on your Mac to use with a screen saver, you put them in your own account at:
/Users/your-user-name/Pictures
Okay. Here's how to change the lock screen image (sort of).
Create and save any image in PNG format at the pixel dimensions of your screen. Name it:
lockscreen.png
Go to this folder:
/Library/Caches/Desktop Pictures/6E3B6E9A-9950-4969-ADC4-535FAAE69D4F/
The long folder name after Desktop Pictures may be different than mine. You should find a file in there already by the name of lockscreen.png. Replace it with your image.
Here's the "sort of" part. If you choose Lock Screen from the Apple menu, you'll just get the same image as your current desktop background. But if you choose Log Out user_name, then you'll see the image you placed in that folder.
Save a copy of your image, because if you change your desktop background, the OS will automatically replace lockscreen.png with a copy of your new desktop image. Then you'll have to replace the file again with your preferred lock screen image.
That's as close as I can find to what you're trying to achieve.
Flycast47 wrote:
The issue not so much having to look at the image but the ability to personalize a feature that had long been accessible on OS X.
Generally nobody cares about these personalization features. Apple has pruned away many of them over the years and the worst thing that ever happened was some long-time user like yourself noticing it once every few months.
On the other hand, any kind of security exploit, no matter how impossible to implement and regardless of theoretical status, will be headline news the next day. So personalization features take a back seat to security.
It seems odd that Apple felt the need to place the management of that particular image display in an inaccessible System folder.
It's not even in a system folder. It is in system firmware that gets loaded before the system folder is decrypted.
I wonder if they are concerned that nefarious codes could be embedded in jpeg, HEIC or PNG files thereby permitting unauthorized clandestine access to the system?
That is exactly the risk. Apple even has a feature to display a login banner to display various scary government warnings about login or whatever. That isn't even a personalization feature. That could be a legal requirement in some locations. But when FileVault is enabled, even the login banner has to wait until that first password to decrypt the disk.
that's strange. i've been marked "solved" many times by the OPs, and also "recommended by apple" a few times as well with that response.. i have this as my setup on my iMac, and it always works.
have you tried this other solution?
1. System Preferences > Users & Groups.
2. Open lock to make changes.
3. Right click on user in left column > Advanced Options.
4. Copy UUID value.
5. Go to /Library/Caches/Desktop Pictures.
6. If it doesn't exist create Desktop Pictures folder.
7. Inside Desktop Pictures create folder with UUID value as name.
8. Right click on folder > Get Info.
9. Open lock to make changes.
10. Grant permission to Read & Write to user, admin, everyone.
11. Make sure FileVault and Guest user are deactivated.
12. Change desktop wallpaper.
13. Restart computer.
Big Sur will now always create a lockscreen.png file in the UUID folder matching the current wallpaper.
i forget who originally posted this. but it also requires a single user setup, and file vault off.
My original question was correct and to the point. Access to any file in the System/Library/DesktopPictures is locked and permissions cannot be changed via the Info window or using Terminal.
[Edited by Moderator]
Booting into Recovery mode and using Terminal is how I disabled system integrity settings. Doing this does not unlock control of permissions to the Library folder. Freeing up drive space is not the objective, changing the hideous Lock Screen background is.
Altering the SIP is not suggested and is dangerous
Flycast47 wrote:
Do you have only one account on your Mac?
On most of my Macs. However, even with more than one user the lock screen is the same as the desktop. As I mentioned, the log in screen is different and I assume is the one you want to change.
jeffreythefrog wrote:
if you are the sole user (not even a guest account) AND file vault is turned off you can go to System Preferences > Users & Groups > Login Options and set "Display login window as" to "List of users". then your login screen matches your desktop background.
Not on mine it doesn't.
jeffreythefrog wrote:
have you tried this other solution?
No. For one thing I rarely ever see the log in screen. and for the 5 seconds or so it takes me to type in my password, I can live with the colorful abstract screen.
Flycast47 wrote:
the hideous Lock Screen background.
It sounds like you are talking about the Login screen background, not the Lock Screen background.
The Lock Screen background is the same as your desktop background. Change that in System Preferences > Desktop & Screen Saver > Desktop
The Login screen is different. If you are using FileVault, then give up. It can't be changed by any means. If you turn FileVault off, then one of the hacks on the internet might work. Might not too. Ultimately the bigger question is how long do you spend each day staring at the login screen. Macintosh computers are expensive. Why pay for one and then let it sit there with the login screen all day?
dialabrain wrote:
No. For one thing I rarely ever see the log in screen. and for the 5 seconds or so it takes me to type in my password, I can live with the colorful abstract screen.
i whole heartedly agree. :) how much time do we actually spend looking at the login screen? maybe a total of 1 minute a week? i'm just trying to help others who DO have an issue with the login screen. :)
You are correct that screen is the Login screen. The issue not so much having to look at the image but the ability to personalize a feature that had long been accessible on OS X. It seems odd that Apple felt the need to place the management of that particular image display in an inaccessible System folder. I wonder if they are concerned that nefarious codes could be embedded in jpeg, HEIC or PNG files thereby permitting unauthorized clandestine access to the system?
System/Library/DesktopPictures
