Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
This usually happens when Word is signed in with a different Microsoft account from the one used for the purchase, or the Mac has retained an old Office license.
Here are some suggestions you can try:
Go to https://account.microsoft.com/services and sign in with the email address used to purchase Microsoft 365. Confirm that the subscription appears as active. If it is not listed, try any other Microsoft account you may have used.
Open Word, select Word > Sign Out, and quit Word completely by pressing Command + Q. Reopen it, select Sign In, and use the same account that shows the active subscription. Word should check the license automatically, so a product key is normally not required.
If the activation message remains, close all Office apps and run the official Office License Removal Tool for Mac. Restart the Mac, open Word, and sign in again with the licensed account. This clears an incorrect or outdated license without deleting your documents.
If Microsoft 365 was purchased through Apple, also verify that the subscription is active under the Apple account used for the purchase.
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