Direct yourself to the following path: HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Common\Identity Right-click the folder item and choose Delete .
and launch Word to check if the preview banner is gone.
Remove the expired key using those 5 characters: cscript ospp.vbs /unpkey:XXXXX (Replace XXXXX with your characters) Step 2: Activate with a Valid Key
Method 2: Uninstall Preview and Install Full Version (Recommended)
For users with a valid LTSC 2021 volume license but who accidentally installed the preview.
: In the same elevated Command Prompt from Step 1, run: cscript ospp.vbs /inpkey:YOUR-PRODUCT-KEY cscript ospp.vbs /act Step 3: Full Reinstallation (Recommended)