Office Home & Business 2019 for Mac – Activation fails with Error 0x0 / "License Not Activated" (same issue as thread 5946261)

Question

Dear Microsoft Support,

I'm experiencing an Office activation failure that matches exactly the issue reported in this thread: https://learn.microsoft.com/en-us/answers/questions/5946261/office-home-business-2019-for-mac-activation-failu

Product Information

• Product: Office Home & Business 2019 for Mac (Perpetual License)
• Microsoft Account: ******@gmail.com
• Product key was redeemed on setup.office.com on April 11, 2024 (confirmed via "TokenAlreadyRedeemedBySameMSA" when re-entering the same key)
• MacBook Air M1

Problem

Word/Excel/PowerPoint show "License: Not Activated" or "StatusStrings/NoLicense" in About, and when trying to activate manually, I get:

Unknown Error, Error Code: 0x0

Troubleshooting already performed

• Verified the license is tied to my account (setup.office.com confirms it, redeemed since 2024)
• Cleared Keychain/Passwords entries related to Office
• Ran the official Microsoft License Removal Tool
• Fully uninstalled all Office apps (Applications + Library/Containers + Group Containers)
• Reinstalled fresh from account.microsoft.com/services — this installed version 16.106, which showed "StatusStrings/NoLicense"
• Downgraded manually to version 16.78.3 (23102801), which several community threads confirm is the last build compatible with Office 2019 perpetual licenses
• Disabled Microsoft AutoUpdate auto-updates to prevent reverting
• Signed out and signed back in with ******@gmail.com
• Still get "Unknown Error 0x0" during activation on 16.78.3 as well

Request

Could you please verify that my Office Home & Business 2019 for Mac entitlement is correctly associated with ******@gmail.com, and check whether there's a known server-side licensing issue currently affecting perpetual Office 2019 Mac activations (as suggested by the other identical report above)? If needed, please escalate to the Licensing/Activation engineering team.

Thank you.Dear Microsoft Support,

I'm experiencing an Office activation failure that matches exactly the issue reported in this thread: https://learn.microsoft.com/en-us/answers/questions/5946261/office-home-business-2019-for-mac-activation-failu

Product Information

• Product: Office Home & Business 2019 for Mac (Perpetual License)
• Microsoft Account: ******@gmail.com
• Product key was redeemed on setup.office.com on April 11, 2024 (confirmed via "TokenAlreadyRedeemedBySameMSA" when re-entering the same key)
• MacBook Air M1

Problem

Word/Excel/PowerPoint show "License: Not Activated" or "StatusStrings/NoLicense" in About, and when trying to activate manually, I get:

Unknown Error, Error Code: 0x0

Troubleshooting already performed

• Verified the license is tied to my account (setup.office.com confirms it, redeemed since 2024)
• Cleared Keychain/Passwords entries related to Office
• Ran the official Microsoft License Removal Tool
• Fully uninstalled all Office apps (Applications + Library/Containers + Group Containers)
• Reinstalled fresh from account.microsoft.com/services — this installed version 16.106, which showed "StatusStrings/NoLicense"
• Downgraded manually to version 16.78.3 (23102801), which several community threads confirm is the last build compatible with Office 2019 perpetual licenses
• Disabled Microsoft AutoUpdate auto-updates to prevent reverting
• Signed out and signed back in with ******@gmail.com
• Still get "Unknown Error 0x0" during activation on 16.78.3 as well

Request

Could you please verify that my Office Home & Business 2019 for Mac entitlement is correctly associated with ******@gmail.com, and check whether there's a known server-side licensing issue currently affecting perpetual Office 2019 Mac activations (as suggested by the other identical report above)? If needed, please escalate to the Licensing/Activation engineering team.

Thank you.

Answer 1

The the error you are seeing is caused by an update on the 13th of July, many people are seeing the exact same error (0x0) if your version of Office is 2019, after that update it is no longer possible to update the security certificated on that version of Office, your Office apps will go into Read Only mode, on the link below they provide full details on that update.

https://support.microsoft.com/office/update-microsoft-365-or-office-on-your-macos-or-ios-device-f418ae5d-bb5f-4078-b3d9-9340f5dd084e