Open a command prompt with administrative permissions.
Go to %installdir%%Program Files%Microsoft OfficeOffice15. If you installed the 32-bit edition of Office 2013 on a 64-bit operating system, %Program Files% is the Program Files (x86) folder.
At the command prompt, type ospprearm.exe. If the rearm succeeds, the following message displays: Microsoft Office rearm successful.
Open a Command Prompt window, and then take one of the following actions
If you installed the 64-bit version of Office 2013, move to the following folder: C:Program FilesMicrosoft OfficeOffice15
If you installed the 32-bit version of Office 2013, move to the following folder: C:Program Files (x86)Microsoft
Display Office Licences
cscript ospp.vbs /dstatus
Remove Office Licences
cscript ospp.vbs /unpkey:<last five characters of product key>
Adds Office Key
cscript ospp.vbs /inpkey:value
Activates an installed Key
cscript ospp.vbs /act
Rearm Office Licence
Microsoft Pages: https://technet.microsoft.com/en-us/library/ee624350.aspx