Share via

Where do I find product key for Microsoft 365 Family subscription? Family member prompted for product key when opening Excel.

Diane Snyder 40 Reputation points
2026-01-13T23:47:15.2966667+00:00

I have a Microsoft 365 Family subscription being shared with 5 family members. One member got a new laptop and installed Microsoft 365 but is prompted for a product key when opening Excel. Where do I find the Microsoft product key?

Microsoft 365 and Office | Subscription, account, billing | For home | Windows
Answer accepted by question author
  1. Stefan Blom 338.7K Reputation points MVP Volunteer Moderator
    2026-01-14T00:35:20.1066667+00:00

    No product key can be used for second or subsequent installations of Office. The key, if you had one, was only for the initial setup.

    Did you invite your family member to share your subscription? See https://support.microsoft.com/en-us/office/share-your-microsoft-365-family-or-premium-subscription-b389b9ce-3ae3-4a82-9017-39d79972fcba.

    And did your family member then follow the steps at https://support.microsoft.com/en-us/office/someone-invited-you-to-share-their-microsoft-365-subscription-6a6c098e-1934-4436-9a94-69c92590da5b to accept the invite and install?

    1 person found this answer helpful.
Answer accepted by question author
  1. Jeronimo Fuerte 38,485 Reputation points Independent Advisor
    2026-01-14T00:24:24.34+00:00

    Hi! Microsoft 365 is a subscription-based service, so you normally don’t need a product key. To activate the apps, just open any Microsoft 365 app (Word/Excel/Outlook) and sign in with the Microsoft account that has the active subscription.

    You can usually do this by clicking the profile circle in the top-right corner and selecting Sign in (or Switch account). If you’re not sure which account owns the subscription, confirm it here: account.microsoft.com/services.

    1 person found this answer helpful.

0 additional answers

Sort by: Most helpful
Most helpful Newest Oldest

Your answer

Answers can be marked as 'Accepted' by the question author and 'Recommended' by moderators, which helps users know the answer solved the author's problem.