On Sierra new Mac, can I partition drive & dual run with an older OS?

[wix1]

Hey All

I have a new Mac running Sierra 10.12.6. Is it possible on this machine to partition the drive and install an older OS to have the option of dual booting? I'm having some issues with some software (photoshop CC 2017 namely), which work fine on previous OS's. Any help would be appreciated.

 

[Fishrrman]

Which "new Mac" do you have?

It may require Sierra to run.
If that's the case, it won't boot from earlier versions of the OS.

And if that's the case, you would probably have to install some kind of virtual machine by which to run the older OS...

 

[wix1]

Which "new Mac" do you have?

It may require Sierra to run.
If that's the case, it won't boot from earlier versions of the OS.

And if that's the case, you would probably have to install some kind of virtual machine by which to run the older OS...

Hi, It's an iMac Retina 21.5" 2017 model.

 

[CoastalOR]

Hi, It's an iMac Retina 21.5" 2017 model.

Fishrrman got it right in his post. The oldest OS your iMac can run is macOS Sierra 10.12.4. Partitioning your iMac to install a older OS and boot from it will not work.