Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
The key has already been redeemed to a Microsoft account. After that, Office Home 2024 is activated by signing in with the same Microsoft account used during redemption, not by entering the key again.
Based on the messages described:
- Do not use Windows activation Settings > System > Activation > Change product key is for Windows, not Office.
- Do not keep retrying the key on setup pages The message "This code has already been redeemed" means the key was already added to an account. The message "This product key was redeemed by [different account]" means Office Home 2024 is attached to that other Microsoft account.
- Use the Microsoft account that redeemed the key Sign in to Office with the Microsoft account that originally redeemed the Office Home 2024 key. If the wrong account is signed in, Office will continue showing Microsoft 365 prompts or fail to activate the purchased product.
- Install from Services & subscriptions, not from the key page After a key is redeemed, the correct place to install is Services & subscriptions: Services & subscriptions
- If Office Home 2024 is not shown there That means the product is not attached to the currently signed-in account. In that case, sign out and check the other Microsoft account that the redemption message identified.
- If the PC came with Microsoft 365 prompts A new PC often includes only a Microsoft 365 trial screen. That does not mean Office Home 2024 is missing; it means the preinstalled apps are still tied to the trial experience until the correct purchased license is used.
- If Office still keeps showing Microsoft 365 after signing in with the correct account Remove the existing Office installation, restart Windows, then reinstall Office from the correct account’s Services & subscriptions page. Uninstalling Office removes the apps, not Word or Excel files.
- If the account mismatch cannot be resolved Use the Microsoft account recovery guidance to identify which account is associated with Office.
The key point is:
- A redeemed Office Home 2024 key cannot be redeemed again
- Office must be installed and activated from the Microsoft account that redeemed that key
- If redemption happened under a different Microsoft account, the current account will not show Office Home 2024
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