microsoft office from microsoft 365 will not load

Micheal Matthews 0 Reputation points
2026-09-06T19:14:40.1+00:00

i purchased a subscription from microsoft for microsoft 365 but when i try and run office it said invalid key for office 2021

Microsoft 365 and Office | Install, redeem, activate | For home | Windows

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  1. Kai-H 26,135 Reputation points Microsoft External Staff Moderator
    2026-09-09T10:31:06.3533333+00:00

    Hi, Micheal Matthews

    This usually means an older Office 2021 installation is still installed and is asking for its original key. A Microsoft 365 subscription normally activates by signing in with the Microsoft account used for the purchase, not by entering an Office 2021 key.

    Here are some suggestions you can try:

    Sign in to your Services & subscriptions page and confirm that Microsoft 365 appears as active. Make sure you use the same email address used for the purchase.

    Open Word, select File > Account, sign out of any listed accounts, close all Office apps, and reopen Word. Sign in with the account that owns the Microsoft 365 subscription.

    If Office 2021 appears under Product Information, you likely have the wrong or an older Office installation. Uninstall Office 2021 using the Microsoft 365 uninstall troubleshooter, restart the computer, then reinstall Microsoft 365 from the Services & subscriptions page. Removing Office will not delete your documents.

    If it still fails, please provide the exact error message and a screenshot of File > Account, with your email address and product key hidden.

    Thank you for your patience in reading, I hope this information has been helpful to you. 


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