Ventura 13.4.x - Setting Error - The operation couldn’t be completed. (com.apple.extensionKit.errorDomain error 15

@Barbey-15E: I appreciate you response; however, there have been lots of complaints about this on this forum and Google, etc. Please do a search on

"Setting Error - The operation couldn’t be completed. (com.apple.extensionKit.errorDomain error 15)"

to prove what I am claiming.

For example: ExtensionKit Error 15 - Apple Community

This is not a hardware or disk failure related issue, but it might be hardware related. I am in a growing number of folks with Intel that are seeing this problem. (Mine is an iMac 27" Intel 3.6 i9 10-core with AMD Radeon Pro 5700)

I am long past the point of going into Safe Mode and Recovery Mode and doing everything possible, plus (via terminal) replacing various pref and cache files.... and the very LAST thing I will do is wipe my disk and start over. We have been rock-solid all the way through Monterey... and these issue started with Ventura.

This next week I might force (via Time Machine) a downgrade back to Monterey...but I am waiting for feedback from the developers (via a great Senior Support engineer) who are helping diagnose the issue. Stay tuned....

The hard part with this issue is that it is somewhat transient. In general, the fixes are not consistent from one person to another. None of the mentioned "fixes" worked for me, and I've tried many of them numerous times.

It's my belief that there is something wrong in the ".extentionKit" code someplace.

The explanation of what we are trying to do is simple. We upgraded an iMac (Intel 27" i9 10-core@3.6 72GB) from the latest Monterey version two weeks ago. Everything went as expected. Shortly after we began to notice some obvious anomalies.

1) Swiping (gesturing) between desktops would freeze the UI if you were doing it aggressively (fast). Everything frozen, even the seconds on the task bar clock. Sometimes it would come back after 4+ minutes. Mostly the screen would turn black and you would be returned to the log-in screen. All of your apps relaunching. The system did NOT crash. I personally think the Finder crashed.

2)Time Machine: This is where we really noticed issues. We wanted to change our Time Machine target Disk to a new NAS volume. It is currently on a NAS volume, but we just added a new NAS and need to change the target. So, I went into System Settings>general>Time Machine. The screen comes up blank. No way to make any changes; however, Time Machine in the task bar was still functional.

3) In an attempt to diagnose this, I wanted to create a test-user and see if this was specific to my account or system wide. So, settings>Users & Groups. This produced the aforementioned error message. Not able to see even my account.

4) After clicking around I found I get the same error in about 20% of the setting apps. For example: clicking on my Apple ID at the top produces that same error.

5) Rest assured we have tried most of the obvious...NVRAM/pram, recovery mode Disk Utility>first aid, reinstalling 13.4.1, reconstructing various cache and pref plists, etc. The problem is still present in Safe Mode.

My personal opinion is that there is an incorrect payload (problem) in some preference/cache plist file that com.apple.extentionKit.plist is trying to deal with. These files tend to be very dynamic, which might explain why some fixes work for some people.

I think I found the issue, although it was not that easy... Everything seems to be working in the Setting again... This is what I sent to Apple Support:

[Spending days looking around, I was able to see (with the help of the Console.app) some strange entries when brining up setttings>Users & Groups. There were complaints from the “address book” (AKA “Contacts”). I launched “Contacts.app”… It should have had about 650 entries, but for some reason it had almost 4,000+ entries. Simply trying to remove duplicates using the “contact>card>Look for Duplicates”, and running it about 5 times, removed a ton of these duplicates. I also cleaned up some renegade entries that made absolutely no sense. 

After the above action I tried to bring up the Settings>Users & Groups pane… and it worked, but “settings>Apple ID” still did not.  From there I created a new user (“testme”) and added administrator permissions. Then, I rebooted and logged-in as  “testme”. I did NOT setup or attach any Apple ID with this new account. I brought up the Systems Setting panel and everything seemed to work with no errors. I then logged out of “testme” and logged into my account “scotts”. I first checked Users & Groups and it functioned as expected. Then I clicked on “Apple ID”, and it finally come up as normal! ]

So, at the very least, the address book was corrupted and fixing it seemed to fix many other things.

This whole thing started with the migration from Monterey to Ventura.

Once on Venture, I was not able to launch the Users & Groups setting, so I could not create a new user at all.

I agree with the re-installation of OS.. useless; however, that is what an Apple Senior advisor insisted that I do. I did NOT Erase all Content and Settings EVER!

Let's be clear what I actually did to solve the problem:

1) Launch the Console.app. Click "start".

2) Launch System Settings...

3) Click on the sub-panel item (in this case Users & Groups).

4) Quickly click on "pause" on the Console.

5) Inspect for any item that show warnings or errors (orange or red dot).

6 Found the form of anything with Users & Group, in this case "UserGroups".

7) Put "UserGroup" in the Console.app search bar.

8) Re-trigger again by clicking "start" and then selecting "Users & Group" in the Settings panel.

9) Inspect the messages again and look at the comments.

10) Found a number of entries that mentioned issues with the "addressbook".

11) Launched the Contact.app and did some maintenance (which is this case was looking for duplicates, etc.).

12) Tried "Users & Groups" again in System Settings... and it now worked.

13) Created a new "testme" account and logged into that account "skipping" setting up an AppleID.

14) Tested all settings including AppleID. All worked with this test account.

15) Logged off of the test account and logged into my account.

16) Test all Settings and no problems found.

Just for fun, try going into "Contacts.app" and running "Card>Look for Duplicates". I am interested to see if this fixes your problem.