Lost my product key 365

Question

Lost my product key 365

After some trojan got in my tower I reloaded office but office wants my product key.

I cannot find it after moving twice.

How do I get back what I am paying for?

Answer 1

Hi,

Please note that this is a public forum, I will be responding you in short period of time and regret for a delay in response. As I am merely a fellow user trying to provide insight and information that may be helpful to others.

I understand how stressful this must be, especially after dealing with a malware issue and reinstalling Office.

For Microsoft 365, you usually don’t need a traditional product key after activation if the subscription is already linked to your Microsoft account. In most cases, your license is tied directly to the account you used when you first purchased or activated it.

Sign in to https://account.microsoft.com/services using the Microsoft account you believe was used for the subscription

Check if Microsoft 365 appears there.

If it is listed, you can simply install and activate Office again while signed in with that same account.

If the issue persists, you may need to reinstall Office to avoid conflicts:

Since you mentioned a trojan infection, it is also a good idea to ensure your system is fully clean before reinstalling and signing back in, to avoid any repeated issues.

In your search bar, type Control Panel and press Enter, then go to Programs > Programs and Features.

Locate the Microsoft 365 subscription or any Office apps installed on your computer, right-click on them, and select Uninstall.

Restart your computer to ensure the changes take effect.

Then reinstall it using the steps below:

Go to https://account.microsoft.com/services

Sign in using the Microsoft account associated with your license.

Locate Microsoft Office and click Install.

This will download the Office installer.

Run the installer and follow the on-screen instructions.

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I’ll be here for your update and ready to help until this is resolved. If you find the answer helpful, please feel free to rate the thread. Otherwise, leave a comment below if there's anything else I can help you with.

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Answer 2

For an active Microsoft 365 subscription, continued use of Office does not depend on keeping the original product key. After the first redemption, the subscription is linked to a Microsoft account, and that account is what is needed to reinstall and activate Office.

To get Office working again without the key:

1. Use the Microsoft account instead of the key
   • Sign in with the same Microsoft account that was used when Microsoft 365 was purchased or first activated.
   • From that account, reinstall Office; activation will be handled by the subscription on the account, not by re‑entering the product key.
2. If a standalone product key was originally used and is now lost or damaged
   • When a product key is damaged but there is valid proof of purchase, Microsoft support may be able to replace the key or offer alternatives. See the guidance under I lost or damaged my product key, then contact Microsoft support via the Microsoft support page and provide purchase details.
3. If the key is lost and cannot be recovered
   • A lost Office/Microsoft 365 product key cannot be viewed from within Office or retrieved from the device.
   • If the key cannot be recovered and there is no proof of purchase for support to work with, the practical option is to buy or try a new Microsoft 365 subscription using the official channels listed under Buy or try Microsoft 365 and follow the safer shopping tips, especially Beware of Product Keys Sold Separately.

Going forward, always reinstall and activate Office by signing in with the Microsoft account that owns the subscription; do not rely on the original key after it has been redeemed.

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References:

• Using product keys with Microsoft 365
• Where to enter your Office product key