OS Reinstall and Do Not Have Original Office 2021 Product Key to reactivate

Question

I had to reinstall MacOS after an issue. I have my license ID but not the original product key from the install. How do I reinstall without the product key for activation. I have the purchase receipt as well.

Answer 1

Hi! Usually the license is linked to your Microsoft account. See the article below in the To install or reinstall Office section.

https://support.microsoft.com/en-us/office/where-to-enter-your-office-product-key-0a82e5ae-739e-4b92-a6f4-2ec780c185db

You can access https://account.microsoft.com/services > Sign in with your Microsoft account > Check if Microsoft Office 2021 is listed. If it is, it's linked to your account. You can expand it and click Install. You can also try the website https://www.office.com/setup

Answer 2

For a retail Office 2021 for Mac license that was properly redeemed in the past, the product key is no longer needed. Reinstallation and activation are done through the Microsoft account that the key was originally redeemed to.

Use these steps:

1. Confirm the license is in the Microsoft account
   • Go to the Microsoft account Services & subscriptions page: https://account.microsoft.com/services
   • Sign in with the same Microsoft account that was used when Office 2021 was first redeemed/installed.
   • Verify that the Office 2021 (or Microsoft 365/Office for Mac) product appears there.
2. Reinstall Office for Mac from the account
   • From the Services & subscriptions page, select the Office product that appears.
   • Select Install to download the Office installer for Mac.
   • Run the installer and complete setup.
3. Activate Office for Mac
   • Open any Office app (for example, Word).
   • When prompted to sign in, use the same Microsoft account that shows the license on the Services & subscriptions page.
   • Activation will complete based on that account; no product key entry is required.

If the product key was never redeemed to a Microsoft account (for example, it was used as a volume/MAK license or tied only to a device and not to an account), then reactivation without the original key is not supported in the provided guidance. In that case, use the purchase receipt to work with the original seller or support channel to recover or replace the license.

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References:

• Reactivate Microsoft 365 or Office
• Activate Office for Mac
• Where to enter your Office product key
• I just bought Office for Home and Business and now "No license found" - Microsoft Q&A

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