If the subscription is active, the installed Office apps usually need to be signed in with the same Microsoft account that owns the subscription.
Try this:
- Go to Services & subscriptions and confirm the Microsoft 365 subscription shows as active.
- Make sure the account signed in there is the same account being used in Word or Excel.
- Open Word or Excel, then go to File > Account and sign in with that subscription account.
- Close and reopen the Office app after signing in.
If the app shows Product deactivated, select Sign in and enter the Microsoft 365 account to reactivate Office.
If the PC came with Office preinstalled and it keeps returning to the Let’s get started page, close all Office apps and reinstall Office from the Services & subscriptions page by selecting Install for the Office product tied to that account.
If activation still fails, check for multiple Office versions installed:
- Open Control Panel > Programs > Programs and Features.
- Search for office.
- If more than one version appears, uninstall the version not being used.
- Restart the PC and sign in again.
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