Once the installation is also complete, you are only a step away from using the Office products. Though you can still use your Office products without even activating, you will miss a lot of premium features. Hence you should activate the complete Office set with your product key. Follow the instructions mentioned down here:

  1. Open an MS Office app on your computer, be it WordAccess, or Excel.
  2. Once the app opens, go to the Microsoft Office icon on the top-left corner to open the menu.
  3. Then click the option saying Word Options.
  4. Now make your way to the Resources option from the left side menu.
  5. Then head to the Activate Microsoft Office section.
  6. Click the Activate button.
  7. You will now redirect to Office.com/setup, and there Microsoft will ask you to enter your Office activation code.
  8. You need to open your registered email and find the email invoice for your Microsoft product.
  9. Locate the key that is made up of 25 unique characters.
  10. Press the Submit button. 
  11. Wait until they verify your product key.
  12. Once that is done, your Office Setup will activate automatically.
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