How to make High Sierra .app file bootable from older Mac

[oscar7601]

Hello everyone,

 

I've used my GF's 2011 MacBookPro to download an original copy of High Sierra. I'd like to make the corresponding .app file bootable so as to be able to use it in unRAID.

 

I've followed this tutorial and it works fine, except for the part where my GF's Mac is running OS X Lion and therefore does not like/support newer MacOS images such as this one.

It is on the desktop, but it seems I can't use the Install Disk Creator software because once I've selected the High Sierra .app file, the icon is crossed and clicking on the "Create Installer" nothing happens.

 

In case this helps, I also have a laptop under Windows 10, should you know of any solution requiring Windows.

 

Could someone please give me a hand in making this file bootable from unRAID (it's supposed to end up as a .img or .dmg file)

 

Thanks a lot in advance.

 

Oscar

[NelizMastr]

Might be a good idea to update your GF's Mac. OS X Lion has been end of support for years, and the 2011 can run High Sierra no problem. 

 

You need OS X mountain lion minimum to work with Sierra and High Sierra installers iirc.

 

You can also try this, if updating somehow isn't an option:

 

https://tylermade.net/2017/10/05/how-to-create-a-bootable-iso-image-of-macos-10-13-high-sierra-installer/

[oscar7601]

On 11/20/2018 at 3:53 PM, NelizMastr said:

Might be a good idea to update your GF's Mac. OS X Lion has been end of support for years, and the 2011 can run High Sierra no problem. 

 

You need OS X mountain lion minimum to work with Sierra and High Sierra installers iirc.

 

You can also try this, if updating somehow isn't an option:

 

https://tylermade.net/2017/10/05/how-to-create-a-bootable-iso-image-of-macos-10-13-high-sierra-installer/

You were right. We paid 21 euros to update the OS to Mountain Lion and I was then able to use the installer for High Sierra  

 

Thank you!

[NelizMastr]

14 hours ago, oscar7601 said:

You were right. We paid 21 euros to update the OS to Mountain Lion and I was then able to use the installer for High Sierra  

 

Thank you!

Wait, you paid for Mountain Lion? Ouch. Could've installed Sierra or High Sierra for free. Now your gf is still on software that's out of support....

 

Anyway, good that it worked.