Product Key Issues

Fix Office 2021 Showing Expired Microsoft 365 Subscription After Key Redemption

Steven Parker Oct 23, 2026 868 views

Question details

The user successfully redeemed an Office 2021 product key, but their Microsoft Office applications continue to display an expired Microsoft 365 subscription warning, and the new license is not easily found in their account.

Fix Office 2021 Showing Expired Microsoft 365 Subscription After Product Key Redemption

Product: Microsoft Office 2021
Device & OS: not provided
Scenario: Redeeming a newly purchased Office 2021 product key to replace a previously expired Microsoft 365 subscription on a computer.
Observed behavior: The activation portal states the key is already used, yet Word and other Office apps fail to recognize the Office 2021 license, instead prompting the user to renew an expired Microsoft 365 subscription.

Before you start

Verify that you are using the exact Microsoft account credentials you used during the setup.office.com redemption process, as product keys permanently bind to the account that is actively logged in at the time of redemption.

Solution 1Recommended

Verify Account License and Refresh Office Login

Confirm that the Office 2021 license is attached to your Microsoft account, then force the desktop applications to recognize the new license by signing out and back in.

Often, Microsoft applications cache the old Microsoft 365 subscription credentials. Refreshing the account login forces the software to ping Microsoft's servers and fetch the newly redeemed Office 2021 perpetual license.

Check Microsoft Services & Subscriptions

Open a web browser, navigate to the Microsoft account Services and subscriptions page, and log in with the email address used to redeem the product key.

Locate the Office 2021 License

Scroll through your active products to verify that 'Office 2021' is listed. If it is, click the 'Install' button next to it to download the correct version.

Sign Out of Office Applications

Open Microsoft Word, click on your profile picture or name in the top right corner, and select 'Sign out'. Close the application completely.

Sign Back In

Reopen Word, click 'Sign in', and enter the Microsoft account credentials associated with your new Office 2021 license. The expired subscription warning should disappear.

Verify Account License and Refresh Office Login

Account Check: If you have multiple email addresses (work, school, or personal), be sure to check the Services and subscriptions page for each one to find where the key was bound.

Solution 2

Contact the Key Retailer or Microsoft Support

If the key shows as 'already used' but Office 2021 is entirely missing from your Microsoft account, the key may be invalid, regional-locked, or previously activated by someone else.

Free Microsoft Office alternative

Switch to WPS Office to Avoid Activation Hassles

Tired of dealing with complex product keys, overlapping subscription conflicts, and expired licenses? WPS Office is a free, lightweight, and powerful alternative that offers full compatibility with your existing Microsoft documents without the activation headaches.

1. Download the Installer: Visit the official WPS website and click the free download button for your operating system.
2. Install WPS Office: Run the downloaded file and follow the simple on-screen instructions to install the suite in minutes.
3. Open Your Documents: Launch WPS Office and directly open your existing Word, Excel, or PowerPoint files to continue working seamlessly.

Fully compatible with Microsoft Office formats including .docx, .xlsx, and .pptx.Free to use with a familiar, user-friendly interface that requires no learning curve.No complicated product key redemptions or frustrating subscription lock-outs.Lightweight installation that runs smoothly on both older and modern computers.

microsoft office alternative - wps office

Frequently Asked Questions

Why does my Office app still show Microsoft 365 when I bought Office 2021?

Office applications often retain the previous subscription license cache. You need to completely sign out of the Office app, and sometimes clear the Office credentials in your computer's credential manager, then sign back in to force the application to recognize the new Office 2021 perpetual license.

What does it mean if setup.office.com says my product key has already been used?

This means the 25-character key has already been bound to a Microsoft account. If you just redeemed it, it is likely bound to the account you were currently signed into. If you have not redeemed it yet and it shows this error, the retailer may have sold you an invalid or previously used key.

Can I have both Microsoft 365 and Office 2021 installed on the same computer?

It is generally not recommended as the overlapping licenses frequently conflict, causing activation errors and expired subscription warnings. It is best to completely uninstall Microsoft 365 and run the Microsoft Support and Recovery Assistant tool before installing your Office 2021 software.

Installation & Activation