My product key seems to have been redeemed by someone else

Question

I just ordered online a Microsoft Office 365 Personal 1-User 1-Year Cd Key Europe 9 and I'm trying to download the product with the key provided by the supplier but the message I get is "This product key was redeemed by w.*******@outlook.com on March 5, 2026 (4 days ago)"

Can you assist?

thanks and rgds,
Eleni Tsipa

Answer 1

1

Where did you purchase the Microsoft Office licence, was that direct from Microsoft or from an online retailer?

2

What edition of Office is that licence for, is that for Office Home 2024, Office Pro plus 2024 or a subscription to Microsoft 365?

Answer 2

The message indicates that the product key has already been redeemed and is now permanently associated with another Microsoft account. A Microsoft 365/Office product key can only be redeemed once and is not meant to be reused or shared.

Next steps:

1. Do not continue trying to redeem or use this key on the current account; it will not work once redeemed elsewhere.
2. Contact the seller from whom the key was purchased and request a refund or replacement, explaining that the key was already redeemed on a different account and providing the error message as evidence.
3. If the seller refuses or appears fraudulent (for example, reselling keys that have already been used), treat this as a potential theft/fraud case and stop using that seller.
4. If there is valid proof of purchase and the situation cannot be resolved with the seller, contact Microsoft Support directly for further assistance and to review options. Use the official support channel at https://support.microsoft.com/contactus/ (from the context) and be ready to provide proof of purchase and the product key.

If the key was bought as a standalone “CD key” from a third-party marketplace, it is possible the key was stolen or otherwise fraudulently obtained and then blocked or reused, which is why the guidance is to resolve it with the seller or seek a refund.

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References:

• Get help with product key errors on Office.com/setup
• Using product keys with Microsoft 365
• "This product key has already been used" error in Office
• "Product key is not valid" error when activating Office
• Theft/Fraud Associated with my Office Product Key. - Microsoft Q&A