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Where can I find High Sierra or Mojave to download

I bought a iMac 27 in. desktop on Ebay. It came with OS catalina. That OS is so buggy I cannot use my machine. I want to downgrade to High Sierra. Where can I find it to download?


iMac Line (2012 and Later)

Posted on Sep 6, 2021 2:23 PM

Reply
Question marked as Top-ranking reply

Posted on Sep 6, 2021 2:24 PM

Helo Lisa,


macOS High Sierra - Technical Specifications


General Requirements

  • OS X 10.8 or later
  • 2GB of memory
  • 14.3GB of available storage to perform upgrade*
  • Some features require an Apple ID; terms apply.
  • Some features require a compatible Internet service provider; fees may apply.

Mac Hardware Requirements

For details about your Mac model, click the Apple icon at the top left of your screen, choose About This Mac. These Mac models are compatible with macOS High Sierra:

  • MacBook (Late 2009 or newer)
  • MacBook Pro (Mid 2010 or newer)
  • MacBook Air (Late 2010 or newer)
  • Mac mini (Mid 2010 or newer)
  • iMac (Late 2009 or newer)
  • Mac Pro (Mid 2010 or newer)
  • Don't use FireFox for these links…

https://support.apple.com/kb/sp765?locale=en_US

https://itunes.apple.com/app/macos-high-sierra/id1246284741?mt=12



macOS Mojave 10.14.6 - Technical Specifications


General Requirements

OS X 10.8 or later

2GB of memory

12.5GB of available storage (OS X El Capitan 10.11.5 or later)*

Some features require an Apple ID; terms apply.

Some features require a compatible Internet service provider; fees may apply.

Mac Hardware Requirements

For details about your Mac model, click the Apple icon at the top left of your screen and choose About This Mac. These Mac models are compatible with macOS Mojave:

MacBook (Early 2015 or newer)

MacBook Air (Mid 2012 or newer)

MacBook Pro (Mid 2012 or newer)

Mac mini (Late 2012 or newer)

iMac (Late 2012 or newer)

iMac Pro (2017)

Mac Pro (Late 2013; Mid 2010 and Mid 2012 models with recommended Metal-capable graphics cards)


Don't use FireFox for these links…

https://itunes.apple.com/us/app/macos-mojave/id1398502828?mt=12


If you get a corrupted message...

Naw, it's not damaged, it's just that you have an old copy already in Applications, there are 2 cures...


Disconnect from the Internet & set the Date back to 2014, then you can run the Install MacsOS ******* App in Applications, so expired Certificates are not expired.


Trash the Install MacsOS *******.app in Applications then a new copy more recent version can be downloaded.

5 replies
Question marked as Top-ranking reply

Sep 6, 2021 2:24 PM in response to lisa cook

Helo Lisa,


macOS High Sierra - Technical Specifications


General Requirements

  • OS X 10.8 or later
  • 2GB of memory
  • 14.3GB of available storage to perform upgrade*
  • Some features require an Apple ID; terms apply.
  • Some features require a compatible Internet service provider; fees may apply.

Mac Hardware Requirements

For details about your Mac model, click the Apple icon at the top left of your screen, choose About This Mac. These Mac models are compatible with macOS High Sierra:

  • MacBook (Late 2009 or newer)
  • MacBook Pro (Mid 2010 or newer)
  • MacBook Air (Late 2010 or newer)
  • Mac mini (Mid 2010 or newer)
  • iMac (Late 2009 or newer)
  • Mac Pro (Mid 2010 or newer)
  • Don't use FireFox for these links…

https://support.apple.com/kb/sp765?locale=en_US

https://itunes.apple.com/app/macos-high-sierra/id1246284741?mt=12



macOS Mojave 10.14.6 - Technical Specifications


General Requirements

OS X 10.8 or later

2GB of memory

12.5GB of available storage (OS X El Capitan 10.11.5 or later)*

Some features require an Apple ID; terms apply.

Some features require a compatible Internet service provider; fees may apply.

Mac Hardware Requirements

For details about your Mac model, click the Apple icon at the top left of your screen and choose About This Mac. These Mac models are compatible with macOS Mojave:

MacBook (Early 2015 or newer)

MacBook Air (Mid 2012 or newer)

MacBook Pro (Mid 2012 or newer)

Mac mini (Late 2012 or newer)

iMac (Late 2012 or newer)

iMac Pro (2017)

Mac Pro (Late 2013; Mid 2010 and Mid 2012 models with recommended Metal-capable graphics cards)


Don't use FireFox for these links…

https://itunes.apple.com/us/app/macos-mojave/id1398502828?mt=12


If you get a corrupted message...

Naw, it's not damaged, it's just that you have an old copy already in Applications, there are 2 cures...


Disconnect from the Internet & set the Date back to 2014, then you can run the Install MacsOS ******* App in Applications, so expired Certificates are not expired.


Trash the Install MacsOS *******.app in Applications then a new copy more recent version can be downloaded.

Sep 7, 2021 3:09 AM in response to lisa cook

Follow the advise from previous posting to determine if the computer can be downgraded.


One can not install an Older version of macOS than what version of macOS it originally can installed with as New.


Once that is done >> How to create a bootable installer for macOS



The Next Steps will Wipe the Entire Drive of ALL DATA - there are no do overs - period.


1 - Shutdown computer and disconnect all external drive Except the newly created Bootable Installer.


2- Restart and immediately hold the OPTION key until the Startup Manager appears and choose the USB Drive. 


3 - It will present options >> Disk Utilities >> View >> View ALL attached Drives.


4 - Choose the Upper Most Drive ( not the volumes indented and list below ).


5 - The drive normally is called Apple Media or Apple SSD - that is the drive to Erase and format as APFS with the GUID Partition Map. 


6 - Once that is done >> backup out of Disk Utilities and choose install macOS. 


7 - Follow the prompts and it may automatically reboot several time. 


8 - Upon a final reboot - Setup Assist will present with the newer version of macOS.


Where can I find High Sierra or Mojave to download

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