I'm looking to get a new iMac, currently using a 27" late 2012. My problem is I still use a lot of old software that won't run on Catlalina. Is it possible to downgrade a new iMac to an older OSX. I currently run High Sierra. If not can an external drive be used on a new machine to boot to an older OSX?
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Downgrade to older OSX on Catalina iMac
- Thread starter imanewmacuser
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You probably won't be able to run High Sierra, but Mojave should run on the current generation.
The currently-sold 2019 iMacs will run fine on Mojave.
This means you can keep using all your older 32 bit software.
You WILL need to erase the internal drive, and "start over", using a bootable USB flashdrive with Mojave on it.
BE AWARE:
If you wait and decide to buy a 2020 iMac, it will come with Catalina as the "minimum boot OS", and there will be no way to do a boot with Mojave (unless you run it under emulation in a virtual machine).
Personal experience:
Like you, I have a lot of older software that won't run under Catalina.
So... I bought a 2018 Mini for the specific purpose of "staying with" Mojave for its entire life, just so I can still use older software with it.
This means you can keep using all your older 32 bit software.
You WILL need to erase the internal drive, and "start over", using a bootable USB flashdrive with Mojave on it.
BE AWARE:
If you wait and decide to buy a 2020 iMac, it will come with Catalina as the "minimum boot OS", and there will be no way to do a boot with Mojave (unless you run it under emulation in a virtual machine).
Personal experience:
Like you, I have a lot of older software that won't run under Catalina.
So... I bought a 2018 Mini for the specific purpose of "staying with" Mojave for its entire life, just so I can still use older software with it.
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