User level: Level 1 (46 points)I am trying to upgrade my MacBook Air's MacOS (currently on 26.5.2 (25F84)) to MacOS 27. I keep getting the following error:
Failed to personalize the software update. Please try again.
An error occurred while downloading the selected updates. Please check your internet connection and try again.
What is causing this error and how do I resolve it?
Posted on Sep 15, 2026 4:04 PM
User level: Level 10 (99,154 points)Sep 15, 2026 6:38 PM in response to jefftb78
Are you running any third-party Anti-Virus, Protecting, Cleaning software or use a VPN on the iMac?
If so, those need to go because they can cause all sorts of bad side effects including blocking macOS updates and upgrades.
If not, try starting up in Safe Mode followed by a Normal restart and then try upgrading the macOS.
User level: Level 10 (123,805 points)Sep 17, 2026 2:55 AM in response to jefftb78
To get around the “ “Failed to personalize the software update” error .
Open Terminal and run: softwareupdate --list
You can also check which full macOS installers are currently available for your Mac:
softwareupdate --list-full-installers
If macOS 27.0 appears in that list, you can download the full installer with:
softwareupdate --fetch-full-installer --full-installer-version 27.0
This downloads the full macOS 27.0 Golden Gate installer, rather than the smaller update package used by Software Update.
If the download completes successfully, a new application named Install macOS Golden Gate.app will be placed in your Applications folder.
You can then open that installer and use it to perform the macOS 27.0 upgrade.
User level: Level 10 (208,430 points)Sep 17, 2026 5:19 PM in response to jefftb78
jefftb78 wrote:
Thanks for the suggestion. I am on 26.5.2 (25F84) and tried to upgrade to 26.7 and received the same error:
Have you run the DiskUtility First Aid on your drive—
Repairs can happen from Recovery if you access the DiskUtility there—
Boot into Internet Recovery (Option Command R) and from the dropdown menu: Utilities> Disk Utility> run the First Aid on your "Macintosh HD-Data" volume, Container, and Parent Drive If errors are found and repaired, run again until no errors reported.
ref: How to repair a Mac storage device with Disk Utility - Apple Support
Disk Utility>View>Show All Devices
User level: Level 10 (99,154 points)Sep 17, 2026 5:44 PM in response to jefftb78
If you have installed any third-party Anti-Virus, Protection, Cleaning software or are using a VPN, uninstall that junk-ware as per the developers directions.
Then try updating and/or upgrading as per the support article instructions.
User level: Level 10 (123,805 points)Sep 17, 2026 2:15 PM in response to jefftb78
If I am not mistaken
The image you have presented would be if you were using the Software Update applet
Using the Terminal command to download the Full Version of MacOS 27 would probably Not Present like in your image
If an error occurred while updating or installing macOS - Apple Support
Check your internet connection
The installer needs a stable internet connection to download macOS and get firmware and other information specific to your Mac model. Make sure that your Mac is connected to the internet.
User level: Level 10 (123,805 points)Sep 18, 2026 2:08 AM in response to jefftb78
To avoid a game of 20 more questions
Download the Application Etrecheck ( External Link ) directly from the Developer.
This is a Diagnostic Tool that makes no changes to the computer.
It makes a coherent and readable inventory of both the Hardware and Software used on the computer
The application is free or paid for added features.
The Report will Not Reveal Any Personal Information.
Post back the Full Report - Share Report >> Copy , then paste >>>> using the Additional Text Icon <<<<
User level: Level 10 (208,430 points)Sep 15, 2026 8:36 PM in response to jefftb78
failed to personalize—
Sign out and back into your Apple Account on Mac
Sign in to or out of your Apple Account on Mac - Apple Support
User level: Level 1 (46 points)Sep 17, 2026 4:21 PM in response to Owl-53
I downloaded the full installer from terminal prompt and then ran it from the Application folder.
Internet connection not an issue.
User level: Level 9 (55,707 points)Sep 15, 2026 11:47 PM in response to jefftb78
Hopefully, you will not need to revive or restore the firmware on that Mac – something which might require the aid of another Mac that is running Apple Configurator.
User level: Level 10 (123,805 points)Sep 17, 2026 5:11 AM in response to jefftb78
jefftb78 wrote:
Thanks for your response. Will this full install cause me to lose any data or settings?
If you have already downloaded the full macOS 27 Golden Gate installer app and your intention is to run that installer to upgrade your existing macOS installation, that is different from an erase-and-reinstall.
If you simply open Install macOS 27 Golden Gate.app and proceed with the installation onto your existing Macintosh HD, it is an in-place upgrade.
Your documents, applications, user accounts, and normal settings are intended to remain in place.
As always make a Time Machine Backup Utility before proceeding
For future purposes
To truly protect your non replaceable Data
Have a 3-2-1 Rescue Plan in place and always current
3 Backups using 2 methods and 1 off site incase of natural disaster or un-natural disaster.
Each of the above should be done to a Dedicated Single Purposed External Drive
Below link is intended to augment what TM Backup does
User level: Level 10 (208,430 points)Sep 17, 2026 8:47 AM in response to jefftb78
jefftb78 wrote:
Thanks for your response. Will this full install cause me to lose any data or settings?
Nothing is lost running the installer.app, it is an upgrade to the new macOS like any other upgrade.
if it automatically launches you can quit the installer until you are ready to run it.
Once downloaded you can manually launch the installer from the Applications folder like any other applications—look for
"Install macOS 27 Golden Gate.app"
User level: Level 10 (99,154 points)Sep 17, 2026 5:03 PM in response to jefftb78
There is something wrong with the current version of Tahoe on your Mac and/or that fetched macOS version is incompatible with your current version.
Go to Apple > System Settings > General > Software Update and Update Tahoe to the latest version, then Upgrade to Golden Gate.
User level: Level 1 (46 points)Sep 16, 2026 5:42 AM in response to den.thed
Nope. None of that. I also tried the upgrade in Safe Mode.
User level: Level 1 (46 points)Sep 16, 2026 5:42 AM in response to leroydouglas
Tried it. Same error. I also tried upgrading while not signed in at all. Same error.
User level: Level 1 (46 points)Sep 16, 2026 5:42 AM in response to Servant of Cats
That is my fear!
User level: Level 1 (46 points)Sep 17, 2026 5:00 AM in response to Owl-53
Thanks for your response. Will this full install cause me to lose any data or settings?
User level: Level 1 (46 points)Sep 17, 2026 9:45 AM in response to Owl-53
I was optimistic this would work! However, the same error:
User level: Level 1 (46 points)Sep 17, 2026 5:10 PM in response to den.thed
Thanks for the suggestion. I am on 26.5.2 (25F84) and tried to upgrade to 26.7 and received the same error:
Originally posted at discussions.apple.com/thread/256357635