I have an iMac 27-inch, late 2013 running Catalina V. 10.15.7. I got a message when I tried to install new software that I need to upgrade to Big Sur v. 10.16 in order to run the software.

️ Do NOT upgrade until you have made a Time Machine or other backup of your startup drive.

Learn How to Back up your Mac with Time Machine

How to Upgrade  macOS:

The macOS version you can upgrade to depends on the year your Mac was released.

Click the  (Apple) menu at the top of your screen and choose About This Mac.

Check the Compatibility of your Mac with newer versions of macOS:

➡️ macOS 11 Big Sur is compatible with the Macs listed here 

➡️ macOS 12 Monterey is compatible with the Macs listed here

➡️ macOS 13 Ventura is compatible with the Macs listed here

✅ - IF your Mac and apps are compatible, then using Safari only, download the macOS upgrade installer app:

Click >  Big Sur,  Monterey  or  Ventura.

Once downloaded, double-click the “Install macOS…” app in the Applications folder to begin the upgrade.

Please see > How to download macOS.

Your computer can't be upgraded past Catalina. Check if there's an older version of the software available.

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