We just started seeing this issue as well, but after updating the version of macOS.app we were using (10.14.4 to 10.14.6) MDS script began working correctly again. One of our guys actually “hacked” his USB by replacing the 10.14.4.app with 10.14.6.app that he had just renamed!
The certificate on the macOS installer has expired. Try double clicking on the installer in the Finder and see if it gives an immediate error. If it says it is damaged, redownload from the app store.
You cannot use the the .app installer to go backwards from the version of the recovery partition. If you run “sw_vers” in recovery, it will show you what macOS version it is. Make sure you are installing that version or later. You can also boot external or boot using command-option-shift-r to go into internet recovery that is an older version.
I added a warning to the current build of MDS 2 to reflect this.
So I cannot use MDS to downgrade macOS, ever? That’s a huge bummer because that’s mainly what I use MDS for (downgrade from Catalina to Mojave).
Aside from that, it would be great to have MDS to check sw_vers automatically before going ahead and erasing the disk, and stop the process if it detects a downgrade attempt. Right now it erases the disk anyway and then just hangs forever, which is not optimal because I’m left with an erased disk with no OS and need to reinstall it using internet recovery, then start all over again. Which wouldn’t be too bad if it wasn’t that every single step in this process takes ages…
That would be a good idea, but I can’t. I need to change the security settings with Startup Security Utility in order to be able to boot from another volume. And in order to do that, I need to authenticate as an admin, which I cannot do on new Macs because there is no account configured. So I would need to go through the whole setup, create an admin account, change security settings to allow boot from another volume, create a bootable USB stick, boot from there, and only then I’d maybe be able to use MDS. So much for saving time and automation!
Sorry I don’t want to be “that person”, I know these are all limitations imposed by Apple and I really like MDS… but I just spent 2.5 hours trying to set up a Mac “the smart way”, nothing is working, and I’m getting pretty frustrated at this point.
This doen’t work either… I get exactly the same sw_vers in internet recovery mode.
You can use MDS to downgrade macOS that is installed on the OS drive, but you can’t downgrade if the macOS you are running recovery is later than the one you are trying to install.
Good suggestion. I’ll look at adding it. Most people are not downgrading, so we don’t see it that much which is why others have not been asking about it.
Are you trying to downgrade a Mac that came with 10.15 but is able to run 10.14? This is most likely the root of your frustrations. Apple really doesn’t want you to do that. If it cam with 10.14, then internet recovery with the command-option-shift-R should go to 10.14. If it came with 10.15, then it goes to 10.14. The workaround is to boot externally, but if it is a new machine, then you have to go through setup assistant to create a user.
I assumed that the recovery version is always the same as the OS version installed, i.e. that if I upgrade macOS, the recovery version also gets upgraded. Are you telling me that, no matter how many times I upgrade macOS on a Mac, sw_vers always stays the same? That’s a small but crucial piece of information
I thought downgrading from 10.5 to 10.4 wasn’t such an unusual thing to do, given all the problems with Catalina and the fact that 32-Bit apps don’t work on it.
Nope. The recovery partition should be the same as the OS that was installed. You can boot to recovery via the internet with different key combos to give you different versions. For example, command-option-shift-R gives the version that was shipped with it (or nearest). Then you can use that version to upgrade to an earlier version that is on the hard drive. For example, if you have 10.15 installed on a 2015 MacBook Pro, you can’t boot to recovery (10.15) and install 10.14. You can, however, internet boot to the macOS version that it came with (perhaps it was 10.13). You can then use MDS to “upgrade” from 10.13 to 10.14.
Perhaps. I just don’t see it that often. I get the question each time macOS updates right around the same time new hardware is released. In fact, I remember issues with downgrading the white iBook caused graphic card issues.
Yup. Apple’s recommendation is to keep 10.15, or buy Macs prior to the new OS dropping. Both are not that great options for some orgs.