Download and install and office setup from enter product key for https://sites.google.com/site/enteroffice25digitproductkey/. log in and enter office 25 digit product key to activate your office product. if you are new user then you need to create a office account to get more benefits of sign in to setup office subscription.If you have a new and never used product key , then this product key can be used during activation process. Go to https://sites.google.com/site/activateoffice365productkey/ with product key and follow the on screen instructions and Enter your Ms office setup from https://sites.google.com/site/microsoftsetupofficecomsetup/ to activate Office.