Can I buy a new Mac mini and install Mojave on it?

[newellj]

Yes a 2018 Mini, it's ok, I will find out after I put the USB in 100% what will or won't install.
I have a ton of time recently.

Did you ever try this? Results? I’m thinking about buying a 2018 Mini but I need to run Mojave (32 bit apps). I’d like to know if this has worked for anyone. My experience has been what the post immediately above describes (version originally installed, rather than version available when the machine was first released).

 

[getrealbro]

Today I did a fresh install of Mojave 10.14.6 on a 16GB or larger USB stick using my 2014 Mini.

Step 1 - Formatted the USB Stick with a GUID Partition map and an AFPS container.

Step 2 - Downloaded Mojave 10.14.6 using my 2014 Mini via the following link
https://itunes.apple.com/us/app/macos-mojave/id1398502828?ls=1&mt=12

Step 3 - Installed Mojave 10.14.6 on the USB stick.

Step 4 - Allowed the Installer to restart and then I minimally configured Mojave with a single account.

At this point I have fresh bootable install of Mojave 10.14.6 which I could clone onto a 2018 Mini’s SSD using Carbon Copy Cloner.

Note: Prior to downloading Mojave, Macs with T2 chips would require disabling some of the startup security to allow booting from external drives (i.e. the USB stick) to complete the install. https://support.apple.com/en-us/HT208198

GetRealBro

p.s. I know this doesn’t answer the question of whether the “current” 2018 Minis are somehow forced to use Catalina. But my bet is that this would work to get Mojave installed on them too.

 

[kibin]

Came here as I can’t downgrade my mac mini 2018 which came preinstalled with Catalina. It just skips booting into mojave usb stick and goes straight to it’s Catalina setup. Nothing works and helps.
Did anyone manage to downgrade?

 

[getrealbro]

Came here as I can’t downgrade my mac mini 2018 which came preinstalled with Catalina. It just skips booting into mojave usb stick and goes straight to it’s Catalina setup. Nothing works and helps.
Did anyone manage to downgrade?

After confirming that I had the correct settings to be able to boot the 2018 Mini from an external drive

About Startup Security Utility on a Mac with the Apple T2 Security Chip - Apple Support

Use Startup Security Utility to make sure that your Mac always starts up from your designated startup disk, and always from a legitimate, trusted operating system.

support.apple.com

I’d try…
1 - Booting the 2018 Mini by holding down the option key during power up to select the Mojave USB Stick
2 - Booting from the Mojave USB Stick on another (pre-Catalina) Mac,

GetRealBro

 

[kibin]

I was able to boot into mojave stick after I’ve set security level to No Security (previously I naively thought that Medium Security will allow me to boot into mojave stick). I’ll post on my progress later

 

[kibin]

Successfully installed mojave from a stick, but after restoring the state from time machine which I made on catalina Safari doesn’t work (with a no sign over it’s icon). Which is a topic of another thread I guess

UPD: fixed safari by installing fresh copy of mojave on a large usb stick, booting from it and replacing corrupted app with those from the stick

 

[!!!]

Update: I did buy a 2018 Mac mini, from B&H when it was on sale a few weeks ago. Came with Mojave.

I had some major issues with the T2 chip not letting me restore my data and ended up with essentially a bricked computer, T2 chip blocked any attempt at installing an OS, and there was no OS on the internal drive. Went to Apple and they ended up replacing the logic board. Interestingly enough, the new logic board came with Mojave installed as well.

Side note: the T2 chip is ****ing stupid. Any data I want to encrypt would already be encrypted in a disk image anyways, please just let me do what I want. (And why support Windows dual-boot and not Linux? I know the real reason, but it almost seems like Linux is more Apple-like than Windows)

 

[Spungoflex]

I was able to boot into mojave stick after I’ve set security level to No Security (previously I naively thought that Medium Security will allow me to boot into mojave stick). I’ll post on my progress later

After all this time, we finally get a straight answer. Good news, as I’m considering a refurb 2017 iMac, but only if I can install High Sierra on it.

Thank you.

 

[kibin]

After all this time, we finally get a straight answer. Good news, as I’m considering a refurb 2017 iMac, but only if I can install High Sierra on it.

Thank you.

As far as I can tell 2017 iMac doesn’t have T2 security chip, which is the main point of pain for those who have it (mac mini 2018 included), so you should be good to go

 

[Synchro3]

As other people here already mentioned, first start the Mac Mini normally in Catalina and create a basic account. Second boot to recovery partition, and enable ,Medium Security' in order to install older systems like Mojave. If you want to start macOS from an external NVME drive or USB stick allow booting from external media.

About Startup Security Utility on a Mac with the Apple T2 Security Chip - Apple Support

Use Startup Security Utility to make sure that your Mac always starts up from your designated startup disk, and always from a legitimate, trusted operating system.

support.apple.com

Download Mojave and create an USB-Installer-Stick:

macOS Mojave Mac App Store direct link: https://apps.apple.com/ch/app/macos-mojave/id1398502828?mt=12

How to create a bootable USB-Stick: https://support.apple.com/en-us/HT201372

 

[Shebco]

Thanks for all the great feedback here. I was successful in rolling back my 2018 Mac Mini to Mojave. All is working as expected!

 

[crowe-t]

I'm about to install Mojave on a 2018 Mac Mini I just bought. It has an i3 processor and came with Big Sur. I bought it new from B&H Photo.