I seem to have lots of Storage and Memory on my computer, but when I check for updates, nothing comes up and when I try to separately download Monterey I get an error saying Update not found. The requested version of macOS is not available.
iMac (2017 – 2020)
Are you running any VPN, Anti-Virus, or Cleaning apps?
The model year of an iMac is available at Apple menu > About This Mac.
A mid 2014 and late 2014 iMac can be upgraded to the latest version of Big Sur macOS 11 but no later. See: How to download and install macOS - Apple Support
A late 2015 iMac can be upgraded to the latest version of Monterey macOS 12 but no later. See: How to download and install macOS - Apple Support
A 2017 iMac can be upgraded to the latest version of Ventura macOS 13 but no later. See: How to download and install macOS - Apple Support
A 2019 or later iMac can be upgraded to the current version of Sonoma macOS 14. See:How to upgrade to macOS Sonoma - Apple Support
Can't upgrade past macOS Big Sur 11.7.10
