macOS Updates: Can't Connect to Software Update Server

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djvan Author

Level 1

52 points

macOS Updates: Can't Connect to Software Update Server

I am trying to update my macOS but it cannot connect to the update server. If I visit:

Apple > About This Mac > Software Update

"Unable to check for updates

Can't connect to the Software Update server (127.0.0.1)."

This is a self-imposed problem that I can't seem to reverse. Years ago I found a post that modified an OS file that resulted in OS update notifications being disabled. What I didn't realize was the modification also disabled my ability to manually update the OS, so I've gone quite awhile without any updates.

Does anyone know how to reverse this file change? Or perhaps a different way to update my iOS? Hoping to find a way to update without needing to wipe the drive with a fresh OS install (I just don't want to lose my programs & files).

macOS Big Sur

Version 11.2.2

I know this is a problem I created; learned my lesson. Please withhold patronizing comments and I thank you for any help.

MacBook Air 13″, macOS 12.3

Posted on Oct 7, 2022 4:46 AM

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Answer 1

Top-ranking reply

Owl-53

Level 10

102,529 points

Oct 7, 2022 5:04 AM in response to djvan

To reverse this command - I Do Not Know but -->>

Terminal Command below without the Quotations Marks

" softwareupdate --list-full-installers "

It will only search for all Full Versions of macOS this Computer Qualifies to run.

What is listed ?

Should it list something like below - Good.

In this case, as the computer is well behind in updates to Big Sur Version 11.2.2 - would suggest moving up to version 11.6.2 first.

Use this Terminal Command again without Quotations Marks

" softwareupdate --fetch-full-installer --full-installer-version 11.6.2 "

This will Pull the Full Version of Big Sur 11.6.2 and place a new application in Applications folder and Will Not Auto Launch.

Just Launch this application and follow the prompts

Once done - just modify the above command and change to a newer Full Installer as list by number.

Be very certain the spacing in command are exacting correct or the command will fail

Title: macOS Big Sur, Version: 11.7, Size: 12118755KiB, Build: 20G817

* Title: macOS Big Sur, Version: 11.6.8, Size: 12118851KiB, Build: 20G730

* Title: macOS Big Sur, Version: 11.6.7, Size: 12121823KiB, Build: 20G630

* Title: macOS Big Sur, Version: 11.6.6, Size: 12121263KiB, Build: 20G624

* Title: macOS Big Sur, Version: 11.6.5, Size: 12121404KiB, Build: 20G527

* Title: macOS Big Sur, Version: 11.6.4, Size: 12147782KiB, Build: 20G417

* Title: macOS Big Sur, Version: 11.6.3, Size: 12143674KiB, Build: 20G415

* Title: macOS Big Sur, Version: 11.6.2, Size: 12141944KiB, Build: 20G314

* Title: macOS Big Sur, Version: 11.6.1, Size: 12137180KiB, Build: 20G224

* Title: macOS Big Sur, Version: 11.5.2, Size: 12149332KiB, Build: 20G95

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Answer 2

dialabrain

Level 10

135,875 points

Oct 7, 2022 4:57 AM in response to djvan

You can try the download link for Big Sur on this page…

How to download macOS - Apple Support

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Answer 3

dialabrain

Level 10

135,875 points

Oct 7, 2022 5:20 AM in response to djvan

Just to add, you may be able to install from Recovery Mode.

How to reinstall macOS - Apple Support

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Answer 4

Owl-53

Level 10

102,529 points

Oct 8, 2022 7:30 AM in response to djvan

Not addressed to me specifically but -->>

" Scorched Earth Method "

This method will WIPE ALL Data and there is No Recovery - Period.

>> Only works on Intel Based Apple Computer <<

To perform this action will require booting from a Bootable Installer.

The Bootable Installer can Only be performed on an Apple Computer

This will have to be performed from a Qualifying Computer to run the version of macOS to be made on the Bootable Installer. Example : Bootable Installer of Big Sur would have to be done on a computer that Qualifies to run Big Sur.

Notation: If the computer being used to perform this action is Too New or Too Old to qualify to run the version of macOS - this computer can not be used.

Alternative is, to gain access to a Qualifying Apple Computer from a family member, friend or associate.

Extra Special Notation regarding the Touch ID equipped Apple Computer.

About Startup Security Utility and Must Enable from Recovery Mode the ability to boot from External Drive Before Attempting

1 - Shutdown computer and disconnect all external drive Except the newly created Bootable Installer.

2- Restart and immediately hold the OPTION key until the Startup Manager appears and choose the USB Drive.

3 - It will present options >> Disk Utilities >> View >> View ALL attached Drives.

4 - Choose the Upper Most Drive ( not the volumes indented and list below ).

5 - The drive normally is called Apple Media or Apple SSD - that is the drive to Erase and format as APFS with the GUID Partition Map. This applies to macOS 10.14 Mojave and above.

5A - Formatting for macOS 10.13 High Sierra and below requires HFS Journaled with the GUID Partition Map

6 - Once that is done >> backup out of Disk Utilities and choose install macOS.

7 - Follow the prompts and it may automatically reboot several time.

8 - Upon a final reboot - Setup Assist will present with the newer version of macOS.

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Answer 5

dialabrain

Level 10

135,875 points

Oct 7, 2022 5:01 AM in response to djvan

If that doesn't work, try running this command in the Terminal…

softwareupdate --fetch-full-installer --full-installer-version 11.7

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Answer 6

dialabrain

Level 10

135,875 points

Oct 7, 2022 5:18 AM in response to djvan

djvan wrote:

What if I used another computer and put the file for macOS Big Sur on a thumb drive. Could I then update my OS from that file, or would it only allow for a fresh install where I lose all files?

You would need a Mac that can download the full Big Sur installer. It shouldn't erase your files but you should have a current Time Machine or other backup in any case.

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Answer 7

djvan Author

Level 1

52 points

Oct 7, 2022 5:09 AM in response to Owl-53

Doesn't work. I think the modification that was made changed the address where OS Updates are retrieved. So it can't connect to the Update Server in any way until the change is reversed. Could be done by either 1) reversing the line of code in the file or 2) replacing the entire file with a functional copy. Issue is I don't know what file it was.

--list-full-installers

Finding available software

Scan finished with error: Error Domain=NSURLErrorDomain Code=-1004 "Can’t connect to the Software Update server (127.0.0.1)." UserInfo={_kCFStreamErrorCodeKey=61, NSLocalizedRecoverySuggestion=Check to make sure your network connection is operating normally. If there are no issues with your connection, contact your network administrator for assistance., NSLocalizedDescription=Can’t connect to the Software Update server (127.0.0.1)., SUErrorUpdateServerName=127.0.0.1, SUErrorRelatedCode=Unknown, _kCFStreamErrorDomainKey=1, NSErrorFailingURLKey=http://127.0.0.1:52232/index-PTCH240484.sucatalog, NSErrorFailingURLStringKey=http://127.0.0.1:52232/index-PTCH240484.sucatalog}

--fetch-full-installer --full-installer-version 11.7

Scanning for 11.7 installer

Scan finished with error: Error Domain=NSURLErrorDomain Code=-1004 "Can’t connect to the Software Update server (127.0.0.1)." UserInfo={_kCFStreamErrorCodeKey=61, NSLocalizedRecoverySuggestion=Check to make sure your network connection is operating normally. If there are no issues with your connection, contact your network administrator for assistance., NSLocalizedDescription=Can’t connect to the Software Update server (127.0.0.1)., SUErrorUpdateServerName=127.0.0.1, SUErrorRelatedCode=Unknown, _kCFStreamErrorDomainKey=1, NSErrorFailingURLKey=http://127.0.0.1:52232/index-PTCH240484.sucatalog, NSErrorFailingURLStringKey=http://127.0.0.1:52232/index-PTCH240484.sucatalog}

Install failed with error: Update not found

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Answer 8

djvan Author

Level 1

52 points

Oct 7, 2022 5:05 AM in response to dialabrain

Tried this. It opens in the App Store but when I click "Get" it opens the Software Update page (Apple > About This Mac > Software Update). The same error is displayed:

""Unable to check for updates

Can't connect to the Software Update server (127.0.0.1)."

What if I used another computer and put the file for macOS Big Sur on a thumb drive. Could I then update my OS from that file, or would it only allow for a fresh install where I lose all files?

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Answer 9

Owl-53

Level 10

102,529 points

Oct 7, 2022 6:43 AM in response to dialabrain

Interesting and just tried the url in above and refer to below which is what you are saying happens.

So whatever was changed in whatever files you used while in Terminal - perhaps if you provide a Link to where this information was provided from, we may more may not be able to sort this out.

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Answer 10

djvan Author

Level 1

52 points

Oct 8, 2022 7:24 AM in response to dialabrain

I was able to reinstall BigSur from recovery mode but it did not fix the problem. I still get this error when trying to check for software updates:

Apple > About This Mac > Software Update

"Unable to check for updates

Can't connect to the Software Update server (127.0.0.1)."

I couldn't find webpage that described the changes I made. I think at this point I need to do a complete wipe of the drive with a fresh install. Is there a guide for doing this with a thumb drive containing the latest OS? I have a MacBook Pro (13-inch, 2017, Two Thunderbolt 3 ports) which I would guess is compatible with the latest MacOS?

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