User interaction required. An error occurred while installing the selected updates.

This worked! Thank you! It's amazing that you have to be a system administrator, disk owner, and authorized on the drive to apply updates. I had addressed the first 2, but fd241ext had the last piece I was missing. For those struggling with the disk ownership piece, which impacts both System Update and FileVault activation, here is a quick outline of how to fix:

Check if you have a valid disk owner

sudo fdesetup list -extended

If you only get a response with a "(null)", then you do not

Example: (null),EBADDBBC-FB36-4A95-8D74-DACA5FE23281

Note: EBADDBBC-FB36-4A95-8D74-DACA5FE23281 is the UUID, or Universally Unique Identifier, for the account

You can create a new system administrator and disk owner by restarting the Setup Assistant

rm -i "/Volumes/Macintosh HD - Data/private/var/db/.AppleSetupDone"

REBOOT

Go through the first boot setup routine, or Setup Assistant, where you can create an additional account

Login as the new system administrator/disk owner and confirm that the new account is a disk owner

sudo fdesetup list -extended

If you have any "(null)" disk owner accounts, you can remove them by

sudo fdesetup remove -uuid <UUID>

To add your original user account as a disk owner

sudo fdesetup add -usertoadd <USERNAME>

Confirm your original user account is now a disk owner

sudo fdesetup list -extended

You can now logout with the new account, login with the old account, and delete the new account

I had same issue too on one drive, while the other was ok. Like almost all of you the problem external drive is not authorised properly on the Mac you are using.

Remedy is to:

1. Connect external drive to Mac.
2. Boot, and you will be taken to login screen on the Mac original internal SSD. (If not, login and go to "SystemSettings! General! Startup Disk!" to make sure you startup from that original SSD.)
3. Once you do, go to "SystemSettings! General! Startup Disk!" CHOOSE the External and press restart.
4. Voila, if you get prompted to choose the "Admin user" to authorise on the Mac you are using.
5. Do so to affect reboot from the external startup drive and go and do the software updates you needed to instal.

Don't forget, as per step 3 above, you can change your Startup drive back to whatever drive you want.

Did it work for you?

I read about it here: recovery OS install - Apple Community

Can you try if this works to update MacOS? I read it after I clean installed MacOS again :(

The command proposed in that thread "sudo softwareupdate -i -a -R" works if this error is triggered by disk ownership issues, which can easily occur when setting up an external boot SSD. I previously fixed those. Here is the trace what I get when I try the command on my Mac Mini:

Failed to download & prepare update: Error Domain=SUOSUErrorDomain Code=201 "Failed to save user credentials for software update." UserInfo={NSLocalizedRecoverySuggestion=An error occurred while downloading the selected updates. Please check your internet connection and try again., NSLocalizedDescription=Failed to save user credentials for software update., NSUnderlyingError=0x600002379200 {Error Domain=SUMacControllerError Code=7748 "[SUMacControllerErrorCommitStashFailed=7748] Failed to commit stash: [MobileSoftwareUpdateErrorDomain(MSU):MSU_ERR_BOOTPOLICY_FAILURE(43)_1_MobileSoftwareUpdateErrorDomain(MSU):MSU_ERR_BOOTPOLICY_FAILURE(43)_2_com.apple.bootpolicy:7]" UserInfo={NSLocalizedDescription=Failed to save user credentials for software update., SUMacControllerErrorIndicationsMask=0, NSDebugDescription=[SUMacControllerErrorCommitStashFailed=7748] Failed to commit stash: [MobileSoftwareUpdateErrorDomain(MSU):MSU_ERR_BOOTPOLICY_FAILURE(43)_1_MobileSoftwareUpdateErrorDomain(MSU):MSU_ERR_BOOTPOLICY_FAILURE(43)_2_com.apple.bootpolicy:7], NSUnderlyingError=0x600002379320 {Error Domain=MobileSoftwareUpdateErrorDomain Code=43 "Failed to update BootPolicy for splat-only update" UserInfo={NSUnderlyingError=0x600002379380 {Error Domain=MobileSoftwareUpdateErrorDomain Code=43 "bootpolicy_update_local_policy_for_splat_update() failed" UserInfo=0x6000038451c0 (not displayed)}, NSLocalizedDescription=Failed to update BootPolicy for splat-only update, target_update=22E772610a}}}}}

I'm running stock. My problem started when the M1 Mac was released and I used Apple Migration tool from an Intel Macbook which messed up the ownership of the drive. Since then I've only been able to update with terminal and the only solution I've read is that I have to reinstall my Mac which is a pain when you got 1TB of stuff.. It's been almost two years now..

@Apple Can you fix this! its been annoying enough that I can only update my Mac M1 with "sudo softwareupdate -i -a -R" (after a migration from a Intel Mac). But now I can't even use the terminal to update..

[Edited by Moderator]

Same issue also. I have an m2 Mac mini 256gb, I bought an external ssd which I have configured my m2 mini to boot up from my ssd. I also have the same macOS updated on the Mac hard drive also. Now on my ssd user account it won't let me update just says "user interaction required, an error occurred blah blah blah" So I tried changing to my other user account on the Mac drive instead of the ssd drive and I get the exact same issue! Nothing seems to work even though I reinstalled the macOS still the same thing. What's worse is when apple do get these issues, you hardly ever find an appropriate fix for it and if you do its after a long struggle to find it.

Same issue here on Mac Studio tried everything - same issue - Trying to update on external SSD hdd

Yes, same error. Not sure why it is coming. Are you on external SSD?

Same error. M2 Mini booting from external Thunderbolt SSD.

Seems too obvious to them to release a small binary of this patch so everyone can update.

Lame !!!

I also deduced the same. I am not sure how to fix the disk ownership issues. If that gets resolved, I guess it should allow the updates too.

Same. This is security update does not work if running macOS from an external drive. Apple does not seem to bother unless you use stock stock.

Thanks. This looks like the right direction. Where can I find a more complete instruction to go through this? Running set up assistant and removing old owner account look scary to me....