Some time Microsoft Office activation refuse to activate the license and the only simple way to activate it is from Powershell , Activate Powershell as administrator and execute:
For office 2016 : cd "C:\Program Files\Microsoft Office\Office16" For Office 2013 : cd "C:\Program Files\Microsoft Office\Office15"
Then execute script command to change the license key (xxxx…. is your license key):
cscript ospp.vbs /inpkey:xxxxx-xxxxx-xxxxx-xxxxx-xxxxx
To activate the license, execute :
cscript ospp.vbs /act
you can extend the trail grace period for 30 days with this :
cd %SystemDrive%\Program Files\Microsoft Office\Office16
OSPPREARM.EXE
cscript ospp.vbs /dstatus