Software Update failing on High Sierra: (NSURLErrorDomain error -1012.)

Scott Bernard wrote:

Well, we sort of finally found the problem, and I have a painful working solution to get around it, since we can't fix it.

Well, I have to revise my earlier post after further testing revealed some things, and other helpful users gave some really good instruction.

The big discovery since my earlier post:

***ALL High Sierra Clean Installs come with the errors/problem... ...until you restart it once.***

Everything below is revised to reflect this.

We sort of finally found the main problem, and I have a working solution to get around it, since we can't fix it.

If you are on High Sierra and none of the other "(NSURLErrorDomain error -1012.)" threads fixes have worked for you, keep reading.

The Problem:

It seems there is something local stopping connections to at least swscan.apple.com, but we don't know what/where it is in order to fix it in-place. 

Do you have the same problem?

1. First, I suspect you have to be on High Sierra to have this problem. I installed multiple Mojaves and they were all error-free.

2. Second, take a look at these related errors to the main problem. Errors 1-3 are the easiest to test for, but maybe some of the other errors already look familiar.

1) Can't add Google or Yahoo email accounts to Internet Accounts pane.

2) Software Update failing on High Sierra: (NSURLErrorDomain error -1012.) (this thread)

3) iOS 17 iPhone 12 not showing up on 2009 iMac iTunes.*

*make sure you have the latest iTunes version if you test. On High Sierra this should be 12.8.3. For some users, this version never appeared in the App Store software Updates section. Get it here: Download iTunes 12.8.3 for Mac

4) Can't download High Sierra full installer.

5) other unspecified "server" or "connection" errors.

3. Third, do 1-3 occur together? If you have 1 or 2 of the errors, but a 3rd one works fine, you likely don't have the problem described above, and this solution would be overkill.

The Solution:

1. 1. The eventual workaround is to install a clean copy of High Sierra.
   2. Migrate your users and data into the clean copy, but to avoid ugly permissions problems, try following the outline found here: Is there a difference in results between Migration Assistant app and 'Transfer Information' option during OS installation?
   3. The High Sierra installer installs an older version of iTunes. You want to install the latest version of iTunes or you may have device connection issues. On High Sierra this should be 12.8.3. Get it here: Download iTunes 12.8.3 for Mac
   4. Check the App Store software Updates section to see if the error is gone. If it's NOT gone, don't panic, just restart your system once, and check again.

Well, we sort of finally found the problem, and I have a painful working solution to get around it, since we can't fix it.

If you are on High Sierra. and none of the other "(NSURLErrorDomain error -1012.)" thread fixes have worked for you, keep reading. I'll do my best to make this as simple as possible.

The Problem:

It seems there is something local stopping connections to at least swscan.apple.com, but we don't know what/where it is in order to fix it.

Do you have the same problem?

1. First, I suspect you have to be on High Sierra to have the problem. I installed multiple Mojaves and they were all error-free.
2. Second, take a look at this link, first post, and the list of errors. Errors 1-3 are the easiest to test for, but maybe some of the other errors already look familiar. (see note #1 below re: testing error 2). https://forums.macrumors.com/threads/nasty-mystery-high-sierra-connection-problem.2409308/
3. Third, do all 3 occur together? If you have 1 or 2 of the errors, but a 3rd one works fine, you likely don't have the problem described above.

The Solution:

The eventual painful solution is to install a new copy of High Sierra and migrate everything into that one.

However, big double painful issue, some of the brand new High Sierra installations came with the same problem already. I'm not kidding. I can't explain it. I did nothing to the new installations beyond making a login to test them, and they already had the problem/errors. So, you have to test each High Sierra installation for some of the errors in the link above, until you find one that's error free (see note #1 below). The installer file isn't bad itself, because I used the same one to make my error-free installations.

Notes:

1. If you think you have the iTunes/iPhone connection issue (error 2), or you want to test for this error, make sure you have the latest iTunes version for High Sierra, iTunes 12.8.3. The High Sierra installer actually gives an OLDER version that will still fail, even when everything else is fixed. Download iTunes 12.8.3 for Mac
2. When you start installing new High Sierras, and testing them for this problem/errors, DO NOT MIGRATE/TRANSFER IN accounts during installation or setup (you can use Migration Assistant app in Applications/Utilities later on). Make a new account, and make sure it has a different name from any account you intend to migrate in later. If you migrate before you test, depending on how big your accounts are, you could be waiting FOR HOURS to get in, and the system may test bad anyway.
3. The horrible long read of how ths was all figured out can be found here: https://forums.macrumors.com/threads/nasty-mystery-high-sierra-connection-problem.2409308/

BDAqua wrote:

Does it work in the new account?

Good idea I hadn't thought of yet.

I tried both an existing admin account and a new admin account. Same error on both.

BDAqua wrote:

I believe you can delete any with a red X, but do you have a backup?

The last bunch are under "System Roots" and apparently require more work in Terminal than I am comfortable with, in order to remove them.

I had no problem removing the earlier ones that were under "login" and "System".

I always have a backup, btw.

I'm still suffering, and looking for a solution.

From my testing it seems like High Sierra installed on a thumb drive will always be error free, but on an internal or external hard drive, it always has the errors. I can't explain it.

I've installed the unsupported Mojave multiple times on hard drives now, and they always work normal, free of the errors.

I've also used Migration Assistant to bring EVERYTHING over from an error High Sierra system, into a working Mojave system. The errors DO NOT migrate over.

I also tried cloning a working thumb drive High Sierra onto a hard drive, but it won't boot up.

I wanted to try a Sierra system out of curiosity, but I can't get the installer to work right.

BDAqua wrote:

Download the Apple Intermediate Certificates

Apple IST CA 2 - G1 Certificate (direct download)

ALL 19 intermediates?

Can I ditch these while I'm at it? (Image)

Thanks

a brody wrote:

Any Remote Management software in Apple menu -> System Preferences would access it. Talk to the school or company that you last worked with.

Thanks for the reply, but it's my own laptop. No school or work management. I bought it new and it never leaves my hands.