IMAC Late 2012 I7 is not upgrading to El Capitan
Have downloaded El Capitan from the AppStore and tried without succes to install it many times on my IMAC late 2012. Are there any solutions for this problem ?
iMac Line (2012 and Later)
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https://discussions.apple.com/docs/DOC-8811
Note, you cannot install El Capitan on top of Sierra, High Sierra, Mojave, or Catalina. You can use internet restore, after backing up your data to install 10.8 then 10.11 if you are running 10.12 or later.
If you are running 10.13 or later, you need to reformat the drive HFS Extended Journalled if it was formatted APFS before you can install anything older than 10.13.