Updated to Catalina and now my Microsoft 365 is asking for a subscription

I presume from your initial post you already have an Office 365 account.

What happened is your installed version worked under the older OS. It then broke because it's under the minimum version necessary to run in Catalina.

Go directly to Microsoft's download page and get the "without Teams" full installer for version 16.62.

https://docs.microsoft.com/en-us/officeupdates/update-history-office-for-mac

Edit: Your "version" changed while I was typing. You recently noted, it didn't need a subscription. In which case, you had a perpetual license version that no longer runs in Catalina. If you prefer a perpetual license, then do as mrnonaustralianguy noted and upgrade to Office 2021.

Well, unfortunately, these days Office does require a subscription now to activate, or to purchase the software itself (Office 2021 LTSC).

To purchase Office 2021 LTSC, which does not use a subscription, simply Google “buy Office 2021 LTSC macOS”. It is supported in Catalina.

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In that case, your iMac is not supported by Apple anymore.

Have you tried signing into Office? Do you already have a Microsoft 365 subscription? Did you have an older version of Office on your Mac (before 2019 version)?

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I looked it up and there are plenty of places to get the LTSC for not very much, some as little as $10.

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There is no legitimate copy of the LTSC software for $10. You'd be purchasing a cracked/illegal copy.

The lowest price I could find for a legal copy is $398. Otherwise, Office 365 Enterprise is the same thing as a subscription. It then just depends on which features you need or want to determine what you want to spend.

macOS Catalina is not the latest macOS version. Currently, macOS Monterey is, soon to be Ventura.

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They said does not already have a subscription because they didn’t need it. They purchased the standalone LTSC software, which didn’t use a subscription.

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