Office 365 check installed product key

Reference: https://support.office.com/en-us/article/Change-your-Office-product-key-d78cf8f7-239e-4649-b726-3a8d2ceb8c81#ID0EABAAA=Use_a_command-line_script

• Run Command Prompt as adminsitrator
• Run this command

c:\>cscript "c:\Program Files (x86)\Microsoft Office\Office16\OSPP.vbs" /dstatus
<code>

  * Check the last 5 characters of the installed product key
  * Remove the product key with this command. Do NOT leave space between "unpkey:" and the product key "XXXXX"
<code>
cscript "C:\Program Files (x86)\Microsoft Office\Office16\OSPP.VBS" /unpkey:XXXXX 

• Then reinstall the product key

cscript "C:\Program Files (x86)\Microsoft Office\Office16\OSPP.VBS" /inpkey:XXXXX-XXXXX-XXXXX-XXXXX-XXXXX

• After input the new product key, better to run the dstatus again to check it.

<code> c:\>cscript “c:\Program Files (x86)\Microsoft Office\Office16\OSPP.vbs” /dstatus <code>

• Then you could activate the Office software as usual by opening Word or Excel, etc.