Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
A Microsoft 365 product key becomes associated with the Microsoft account used when it is redeemed. It cannot be moved or transferred to a different Microsoft account after activation.
What can be done:
- If the key was already redeemed, stop trying to enter it again. A redeemed key is no longer used for install or activation.
- Sign in with the account that redeemed the key at Microsoft account, Services & subscriptions page to install and activate Microsoft 365.
- If the product was activated on the wrong account and that account should not be used, contact Microsoft Support with proof of purchase.
- If the purchase was a subscription bought through a third party, cancellation may need to be handled through the seller, then repurchased under the correct account.
Useful checks:
- In an Office app, go to File > Account and check the email shown after Belongs to to confirm which Microsoft account owns the license.
- For future installs, use the Microsoft account that redeemed the product key, not the key itself.
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