Microsoft has successfully deployed a fix for a widespread issue causing unexpected “Product Deactivated” errors in Microsoft 365 Office applications. The problem, which affected numerous users across various platforms, was primarily triggered by administrative licensing changes.

The deactivation errors commonly occurred during specific scenarios, including:
– Transitioning from Office 365 E3 to Microsoft 365 E3
– User transfers between licensing groups
– Changes in Azure Active Directory settings
– Modifications to license or service plan configurations

The company has implemented a service-side patch to resolve these unexpected deactivations. For users who haven’t received the update, Microsoft recommends several temporary solutions:
1. Click the “Reactivate” button and complete the sign-in process
2. Sign out of all Microsoft 365 apps, close them, and restart with fresh credentials
3. Verify subscription status through the Microsoft 365 management portal

For persistent issues, users should submit diagnostic logs from the %temp%/diagnostics directory to Microsoft support. This resolution follows recent fixes for other Microsoft 365 issues, including Outlook freezing problems and application crashes related to text editing and spell-checking functions.