Unknown Error 0x0 or License not found error in Microsoft 365 or Office running on macOS

Last Updated: July, 15, 2026

ISSUE

When launching an Office application running on macOS you see one of the following messages:

• Unknown Error 0x0

• License Not Found

STATUS: RESOLVED

If you installed Microsoft 365 or Office from microsoft.com, follow these steps:

1. Ensure that you are running at least macOS version 12 or higher.

2. Close all Office applications.

3. Open the Microsoft AutoUpdate (MAU) from Finder > Applications > Microsoft AutoUpdate.

   Note

   If you don’t see MAU, check /Library/Application Support/Microsoft/MAU2.0/

4. If you want to learn about the details of each update before installing, select the arrow next to the Update button and review the apps, versions and installation date. Then select Update All or Update next to individual apps.

5. After the updates are complete, launch the Office application again to test.

If you installed individual Office apps from the App Store (less likely) follow these steps:

1. Ensure that you are running at least macOS version 12 or higher.

2. Close all Office applications.

3. Open the App Store.

4. Select Updates from the sidebar

5. Look for:

   • Microsoft Word

   • Microsoft Excel

   • Microsoft PowerPoint

   • Microsoft Outlook

   • Microsoft OneNote

6. Select Update next to each app or Update All.

7. After the updates are complete, launch the Office application again to test.

More Resources

See Also

Fixes or workarounds for recent Office installation or activation issues