Hello,
First you can make sure of the licensing before doing any action:
Go to the next folders in CMD depending on the version:
Office 2016 / 2019: C:\Program Files\Microsoft Office\Office16 or C:\Program Files (x86)\Microsoft Office\Office16
Office 2013: C:\Program Files\Microsoft Office\Office15 or C:\Program Files (x86)\Microsoft Office\Office15
Then run:
cscript ospp.vbs /dstatus
*Note the Licensing information to confirm that is changed later.
To remove the licensing use the next command:
cscript ospp.vbs /unpkey:{last five characters of the current product key}
Once this is done, you can open any office application to show the registratioin popups or run the next from command line:
cscript ospp.vbs /inpkey:<full new key including - symbols>
After this, you should be able to run cscript ospp.vbs /dstatus and see how the licensing has changed.
Other ospp.vbs reference and useful parameters: https://learn.microsoft.com/en-us/deployoffice/vlactivation/tools-to-manage-volume-activation-of-office
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