To fix the error, you must transition from the pre-release "Preview" version to the official, commercially released version of Office LTSC 2021 or another supported product.
First, it is vital to understand why this error occurs. Microsoft releases "Preview" versions of LTSC (Long Term Servicing Channel) software to enterprise customers for compatibility testing before General Availability (GA). These preview builds are —programmed to stop functioning after a specific date. The error is not a bug; it is a feature designed to prevent pre-release software from lingering in production environments. Consequently, there is no "patch" or "registry hack" to extend the life of a preview build. Attempting to reactivate an expired preview is like trying to refill a disposable lighter; the mechanism is designed for a single, finite lifecycle. To fix the error, you must transition from
The “Microsoft Office LTSC Professional Plus 2021 Preview has expired” error is a deliberate license restriction, not a malfunction. The only permanent fix is to uninstall the preview and deploy a properly licensed, non‑preview version of Office LTSC 2021 or migrate to a Microsoft 365 subscription. Temporary reactivation methods are unreliable and not suitable for business continuity. These preview builds are —programmed to stop functioning
The "preview has expired" message is a common issue faced by users of the preview version of Office LTSC Professional Plus 2021. This message is displayed because the preview version of the software has a limited lifespan and is only valid for a certain period. Once the preview period expires, the software will no longer function, and users will need to activate a licensed version or upgrade to a newer version. Attempting to reactivate an expired preview is like
If you have a legitimate full version of Office LTSC 2021, you do not necessarily need to uninstall the preview. You can activate it using a valid key. Microsoft Learn : Open any Office app (like Word) > Change Product Key . Enter your MAK (Multiple Activation Key) and select Via Command Prompt (Volume Licensing) Command Prompt as an administrator. Navigate to the Office folder: cd "\Program Files\Microsoft Office\Office16" Enter your product key: cscript ospp.vbs /inpkey:XXXXX-XXXXX-XXXXX-XXXXX-XXXXX cscript ospp.vbs /act University of Wisconsin–Madison 2. Reset the Trial Period (Temporary Fix)
Go to Control Panel > Programs and Features , right-click Microsoft Office LTSC Professional Plus 2021 - Preview , and select Uninstall .