On my late 2013 iMac I get a error 102 when trying to install available updates. My iMac is at OS X 10.8.5 . It says that I need at least OS X 10.9 to install the newest OS X on my computer which is Catalina. But when I do try to install available updates I get error 102. I did a factory reset because I’m selling this iMac.
iMac 21.5″, macOS 10.15
You will likely need to first install macOS 10.11 El Capitan, then later proceed to Catalina. You can find links to various macOS installers within this Apple article which also contains optional instructions for creating a bootable macOS USB installer:
How to create a bootable installer for macOS - Apple Support
I recommend you create the bootable macOS USB installer so you have more options in case something goes wrong during the upgrade.
Make sure to have a good backup before attempting to upgrade macOS just in case something goes wrong.
You should always have frequent and regular backups of your computer and all external media (including the cloud) which contains important & unique data.
Hey Radar88,
We'd suggest trying the steps in this article to see if they help resolve your update issues: If an error occurred while updating or installing macOS - Apple Support
Thanks!
Error 102 when updating from OS X 10.8.5
