Update Office using the same installation source it came from, because Microsoft identifies the Mac activation error 0x0 as a resolved licensing issue whose primary fix is installing the applicable Office updates.^1^
1. Check the macOS and Word versions
“Up to date” can mean that no newer version is available for that particular Mac, so record the actual versions first:
- Select Apple menu → About This Mac and note the macOS version.
- In Word, select Word → About Microsoft Word and note its version.
- Use the matching branch below.
2. Install the applicable Office update
Microsoft’s documented 0x0 update procedure requires macOS 12 or later.^1^
If Office was installed from Microsoft:
- Quit Word and every other Office application.
- Open Finder → Applications → Microsoft AutoUpdate.
- If it is absent, open Finder → Go → Go to Folder, enter:
/Library/Application Support/Microsoft/MAU2.0/
- Open Microsoft AutoUpdate and select Update All.
- Reopen Word and sign in with the Microsoft account that accepted the family invitation.
If Word was installed from Apple’s App Store:
- Quit all Office applications.
- Open App Store → Updates.
- Update Word and the other installed Microsoft applications.
- Reopen Word and sign in again.
Do not mix installation channels: an App Store installation should be updated through the App Store, while an installation obtained from Microsoft should use Microsoft AutoUpdate.
Version-specific cases:
- macOS 14 or later: Use the update procedure above.
- macOS Monterey 12: If AutoUpdate cannot provide a working update, Monterey’s final compatible Office release is reported as version 16.88.
- macOS Ventura 13: If AutoUpdate cannot provide a working update, Ventura’s final compatible Office release is reported as version 16.101.^2^
- Earlier than macOS 12: The documented
0x0 update procedure does not apply. If the Mac cannot be upgraded, use Microsoft 365 in a web browser or another supported device and contact Microsoft Support about available installation options.^2^
3. Verify that the family benefit reached the correct account
This distinguishes an invitation problem from a local Word licensing problem.
- The subscription owner should open the Microsoft 365 sharing dashboard:
https://account.microsoft.com/services/office/sharing
- Confirm that the invited person is shown as a member rather than Pending invite.
- The invited person must open the invitation, select Accept, and then select Join now using the same Microsoft account that will be used in Word.[^3^](https://support.microsoft.com/accounts-billing/subscriptions/[Subscription ID] "Someone invited you to share their Microsoft 365 subscription")
- If that account already belongs to another Microsoft family group, it must leave that group before joining the subscription owner’s group. Sharing works only while the invitee belongs to the owner’s family group.[^4^](https://support.microsoft.com/accounts-billing/subscriptions/[Subscription ID] "Share your Microsoft 365 subscription | Microsoft Support")
- In Word, sign out of any other account and sign in with that exact invited account.
Invitations expire after 48 hours if they are not accepted, in which case the owner must resend one.[^4^](https://support.microsoft.com/accounts-billing/subscriptions/[Subscription ID] "Share your Microsoft 365 subscription | Microsoft Support")
4. If entitlement is present but Word still reports 0x0
Reset the locally cached Office license:
- Ensure the Microsoft account password is available.
- Quit all Office applications.
- Download and run Microsoft’s Office License Removal Tool.
- Open its
.pkg file and complete the wizard. A Mac local administrator password may be required.
- Open Word and activate it with the account receiving the Microsoft 365 Family benefit.
- Restart the Mac after activation.^5^
This tool removes all Office licenses from the Mac, so have the correct account credentials ready before running it.
If the account appears as an active shared member but activation still fails after the applicable update and license reset, contact Microsoft Support and provide the exact macOS version, Word version, installation source, and error code 0x0.
References
- Unknown Error 0x0 or License not found error in Microsoft 365 or Office running on macOS | Microsoft Support
- 0x0 Error After Mac Update July 14th, 2026 - Microsoft Q&A
- [Someone invited you to share their Microsoft 365 subscription](https://support.microsoft.com/accounts-billing/subscriptions/[Subscription ID])
- [Share your Microsoft 365 subscription | Microsoft Support](https://support.microsoft.com/accounts-billing/subscriptions/[Subscription ID])
- How to remove Office license files on a Mac | Microsoft Support