Unable to install apps on iMac (Big Sur) due to macOS version requirement

I'm experiencing an issue when trying to install an app, such as Microsoft Teams, on my iMac (Big Sur). It's giving me a message that the app can't be installed on Macintosh HD because macOS version 12 or later is required. Even though my Mac is up to date, there is no version 12 available yet; the latest version is 11.7.10


[Re-Titled by Moderator]

Original Title: Installing issue

iMac 27″, macOS 11.7

Posted on Oct 30, 2025 12:47 AM

Reply
Question marked as Top-ranking reply

Posted on Oct 30, 2025 3:53 AM

Which 27" iMac do you have? You would need one with a hardware model year of

  • Late 2015 or later to upgrade to macOS 12 (Monterey)
  • 2017 or later to upgrade to macOS 13 (Ventura)
  • 2019 or later to upgrade to macOS 14 (Sonoma) or macOS 15 (Sequoia)
  • 2020 to upgrade to macOS 26 (Tahoe)


If your 27" iMac has a model year of Late 2014 or Mid 2015, Big Sur is as far as it can go.


If you can upgrade, see the App Store links in How to download and install macOS - Apple Support .


Note that Microsoft has a policy of supporting only the three most recent versions of macOS. That means that you may need a Mac running Sonoma, Sequoia, or Tahoe to use the desktop Teams app. If your Mac is too old to clear that hurtle, you may want to try using Firefox and the Teams client for the Web. (The current version of Firefox will run even on Catalina.)


Microsoft – Teams client system requirements

3 replies
Question marked as Top-ranking reply

Oct 30, 2025 3:53 AM in response to emadkhalil

Which 27" iMac do you have? You would need one with a hardware model year of

  • Late 2015 or later to upgrade to macOS 12 (Monterey)
  • 2017 or later to upgrade to macOS 13 (Ventura)
  • 2019 or later to upgrade to macOS 14 (Sonoma) or macOS 15 (Sequoia)
  • 2020 to upgrade to macOS 26 (Tahoe)


If your 27" iMac has a model year of Late 2014 or Mid 2015, Big Sur is as far as it can go.


If you can upgrade, see the App Store links in How to download and install macOS - Apple Support .


Note that Microsoft has a policy of supporting only the three most recent versions of macOS. That means that you may need a Mac running Sonoma, Sequoia, or Tahoe to use the desktop Teams app. If your Mac is too old to clear that hurtle, you may want to try using Firefox and the Teams client for the Web. (The current version of Firefox will run even on Catalina.)


Microsoft – Teams client system requirements

Unable to install apps on iMac (Big Sur) due to macOS version requirement

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.