I'm having issues installing an upgrade to my OS. I currently have 10.9.5, and I am trying to upgrade to Catalina. I downloaded the installer fine but when I try to run it I get as far as the screen saying it will use to Macintosh HD disk, I hit install and nothing happens. It does nothing. I have looked around for a solution online but have found nothing. Hope someone can help.
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Can't update OS on iMac
- Thread starter Evau
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Also, if you have an iMac with a HD rather than an SSD, then don't bother - your iMac will slow to a crawl and you'll end up throwing it out of a window.
e.g. after downloading the installer to 2 iMacs, my 2017 model with an SSD took 30 minutes to install Catalina from Mojave. I did the same install on my old iMac (a 2012 with HD which I've gifted to a family member, but maintain for them) from High Sierra and it took 4 hours, and now takes about 3 minutes to boot up.
e.g. after downloading the installer to 2 iMacs, my 2017 model with an SSD took 30 minutes to install Catalina from Mojave. I did the same install on my old iMac (a 2012 with HD which I've gifted to a family member, but maintain for them) from High Sierra and it took 4 hours, and now takes about 3 minutes to boot up.
I would suggest that you NOT upgrade to Catalina.
Instead, pick an OS version "a little lower", but more advanced than what you have now.
If it was me, I'd pick either Low Sierra (10.12) or Mojave (10.14).
You can upgrade directly to Low Sierra without re-formatting your drive.
You can get the installer here:
support.apple.com
If you want to upgrade to Mojave (or Catalina), you're going to have to erase (reformat) your internal drive first, to APFS.
That means you're going to have to BACK UP the existing drive.
I recommend using either CarbonCopyCloner or SuperDuper to create a BOOTABLE cloned backup of the internal drive.
Both these apps are FREE to download and use for 30 days. This costs you nothing.
DO NOT ERASE THE INTERNAL DRIVE WITHOUT A PROPER BACKUP !!!
Then you need to download the installer and create a bootable USB flashdrive.
You can get Mojave here:
support.apple.com
For Mojave, I'd suggest using DiskMaker X (free) to create the flashdrive.
Then:
- boot from the flashdrive
- erase the internal drive to APFS
- install the OS
- begin setup
- setup assistant will ask if you wish to migrate from another drive. Now connect the cloned backup and proceed.
Instead, pick an OS version "a little lower", but more advanced than what you have now.
If it was me, I'd pick either Low Sierra (10.12) or Mojave (10.14).
You can upgrade directly to Low Sierra without re-formatting your drive.
You can get the installer here:
How to download and install macOS - Apple Support
Download and install current or previous versions of the Mac operating system on compatible Mac computers.
If you want to upgrade to Mojave (or Catalina), you're going to have to erase (reformat) your internal drive first, to APFS.
That means you're going to have to BACK UP the existing drive.
I recommend using either CarbonCopyCloner or SuperDuper to create a BOOTABLE cloned backup of the internal drive.
Both these apps are FREE to download and use for 30 days. This costs you nothing.
DO NOT ERASE THE INTERNAL DRIVE WITHOUT A PROPER BACKUP !!!
Then you need to download the installer and create a bootable USB flashdrive.
You can get Mojave here:
How to download and install macOS - Apple Support
Download and install current or previous versions of the Mac operating system on compatible Mac computers.
For Mojave, I'd suggest using DiskMaker X (free) to create the flashdrive.
Then:
- boot from the flashdrive
- erase the internal drive to APFS
- install the OS
- begin setup
- setup assistant will ask if you wish to migrate from another drive. Now connect the cloned backup and proceed.
