Product Key

The product key is only needed for your first install. After that, visit the Subscriptions page of your Microsoft account and click on the Install link beside the Microsoft 365 listing.

Hi @Ripan Chakma

Thank you for posting question to Microsoft Q&A.

I understand you're trying to activate Microsoft 365 on a new MacBook but are unable to find a product key, which is preventing you from saving files in Word and Excel. This is a very common point of confusion, and I can certainly help clarify the process.

The most important thing to know is that Microsoft 365 subscriptions do not use a product key for reinstallation or activation on a new device. A product key is only used once when you first purchase and set up the subscription. After that, your Office 365 subscription is tied to your Microsoft account, not a specific device.

Here is the correct procedure to get Office running on your new MacBook:

1. On your new MacBook, open a web browser and navigate to the Microsoft Account services page: https://account.microsoft.com/services
2. Sign In: Sign in with the same Microsoft Account (email and password) that you used when you originally purchased or redeemed your Microsoft 365 subscription.
3. Install Office: Once signed in, you should see your active Microsoft 365 subscription listed. Next to it, you will find an "Install" button. Click this button to download the correct Office installer for your Mac.
4. Activate by Signing In: After the installation is complete, open any Office app like Word or Excel.   Simply sign in with your Microsoft Account when asked. The app will detect your active subscription online and will activate automatically. It will not ask for a product key.

Note: Please make sure to sign out and uninstall Office app, then follow the above steps.

This should resolve the issue and allow you to save and edit your files again. I hope this helps you get everything set up quickly

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