If Microsoft 365 or Office shows an activation warning, the safest fix is to identify which product you actually own, sign in with the correct Microsoft account, and activate it through Microsoft’s official setup process.
Important: Microsoft 365 is a subscription product. Office 2024 is available as a separate one-time purchase. Be cautious with websites that advertise unofficial “lifetime Microsoft 365” activators, scripts, keys, or modified installers.
Quick answer
Open a Microsoft 365 app such as Word, sign in with the account used to buy or subscribe, check the Services & subscriptions page in your Microsoft account, and reinstall Office from there if needed. If you bought a new product key, redeem it through Microsoft’s official setup page.
Microsoft 365 vs Office 2024
Microsoft 365 normally uses a monthly or annual subscription. It receives ongoing feature updates and cloud services depending on the plan. Office 2024 is a one-time purchase for a specific device and does not include upgrades to future major versions.
1. Check which product you own
Sign in to your Microsoft account and open the Services & subscriptions section. Look for Microsoft 365, Office Home 2024, Office Home & Business 2024, or another licensed product.
If nothing appears, make sure you are using the same Microsoft account that was used for the purchase.
2. Activate by signing in
Open Word, Excel, or another Office app. If prompted, sign in with the Microsoft account, work account, or school account associated with the license.
Do not sign in with a different personal account just because it is already saved in the browser.
3. Redeem a genuine product key
If you bought a new Office product key from Microsoft or an authorized reseller, redeem it using Microsoft’s official setup process. Once the product is attached to your Microsoft account, install Office from that account.
4. Reinstall from your Microsoft account
If Office was previously activated but no longer works, uninstall the broken installation if necessary and reinstall it from the Services & subscriptions page for the licensed account.
5. Check date, time and internet access
Incorrect system time, blocked internet access, or a restrictive network can interfere with activation. Make sure Windows date and time are correct and that the PC can reach Microsoft services normally.
6. Update Windows and Office
Install available Windows updates and Office updates. Restart the computer and try activation again.
7. Remove conflicting old Office installations
If several old Office editions are installed together, licensing conflicts can occur. Remove versions you no longer use before reinstalling the licensed edition.
8. Check work or school licensing
If Office was provided by an employer or school, the license may depend on that organization. Contact the organization’s IT administrator if the account no longer activates Office.
9. Avoid unofficial activation scripts and cracked installers
Do not use third-party activation scripts, modified installers, or suspicious “lifetime” keys. They can violate licensing terms and may expose the PC to malware or account theft.
10. Use Microsoft activation support if needed
If you own a valid license but activation still fails, use Microsoft’s official activation troubleshooting and support options rather than buying another key immediately.
What not to do
- Do not download Office activators from file-sharing or unknown software sites.
- Do not disable antivirus or Windows security to run an activation tool.
- Do not buy unusually cheap “lifetime Microsoft 365” keys from sellers you cannot verify.
- Do not share your Microsoft account password or recovery codes with a seller.
Frequently asked questions
Can I buy Microsoft 365 for lifetime use?
Microsoft 365 is generally sold as a subscription. If you want a one-time purchase, Microsoft sells Office 2024 editions separately.
Why does Office say Unlicensed Product?
Common causes include signing into the wrong account, an expired Microsoft 365 subscription, a license that belongs to a different organization, or a damaged Office installation.
Can I reinstall Office without buying it again?
If the license is already attached to your Microsoft account and is still valid, you can normally reinstall the product you own from that account.