Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Open Word or Excel and sign in with the same Microsoft account used to purchase Microsoft 365; this normally activates an installed Microsoft 365 for home subscription automatically.^1^
Activate the installed apps
- Open Word or Excel.
- Select Sign in when prompted. If an Activation Wizard appears, follow its prompts.
- Enter the Microsoft account used when purchasing the subscription—not necessarily the account currently signed into Windows.
- Close all Microsoft 365 apps, restart the device, and reopen Word or Excel.
If the purchase included a product key
A product key bought from a retailer or online store must first be redeemed:
- Go to Office.com/setup.
- Sign in with the Microsoft account that should own the subscription.
- Enter the product key and complete the prompts.
- Reopen Word or Excel and sign in with that same account.
Redemption is a one-time process that associates the purchase with the Microsoft account.^1^
Confirm that the subscription is linked
Visit Services & subscriptions, sign in, and check that Microsoft 365 appears under Subscriptions with the correct status.^2^
- Subscription appears as active: Sign out of every Office app, restart the device, and sign back in using that exact account.
- Subscription is missing: Try any other personal email address that may have been used for the purchase. Office cannot activate with an address that has no associated product.
- Subscription is expired or cancelled: Renew it from the same page.
- Retailer purchase is not listed and no key was supplied: Contact the retailer to confirm that the purchase was fulfilled and linked or that a redeemable key was issued.
If Windows still shows “Unlicensed Product”
Microsoft’s activation troubleshooter applies to Windows 10 or later:
- Open Microsoft’s activation troubleshooting page on the affected PC.
- Start the Microsoft 365 activation troubleshooter.
- Allow the page to open Get Help, then complete its prompts.^2^
If activation still fails, check Control Panel → Programs → Programs and Features for multiple Office installations. Remove versions that are not being used, restart the PC, and sign in again. Multiple installations can cause activation conflicts.^2^
As a final Windows repair path, deactivate the existing installation, completely uninstall Office using Microsoft’s removal tool, and reinstall it from the account that displays the active subscription.^3^
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