If your computer does not meet the minimum requirements for Catalina or Mojave, you will not be able to install a supported version of macOS. If you are running an older OS, you can look at the hardware requirements for the currently supported versions of macOS to see if your computer is capable of running them: If you are running macOS 10.11 or newer, you should be able to upgrade to at least macOS 10.15 Catalina. If your computer is running macOS High Sierra 10.13 or older it will need to be upgraded – make a note of your installed macOS version and your computer’s model and year as that information will be helpful when upgrading macOS.You’ll see the macOS name and version number, such as macOS Catalina 10.15.5 as well as your computer model and year.From the Apple menu in the top left corner of your screen, choose About This Mac.
All UVM-owned computers running macOS 10.13 High Sierra or older must be updated or replaced as soon as possible to comply with the University Information Security Policy.