If you receive a Product Deactivated notice while using Office apps, you can reactivate Office by signing in to the Microsoft Account you use with Office 365.
To reactivate Office after you receive a Product Deactivated notice:
Choose Sign in.
Sign in with the email address and password for the Microsoft Account you use with Office 365.
Office will now be reactivated.
Note: You must have an active Office 365 for home subscription and available installs in order for the install to reactivate.
With an Office 365 for home subscription you can install Office on up to five PCs or Macs depending on the plan you have.
If you receive a Product Deactivated notice while using Office apps such as Word, Excel, or PowerPoint it means the install on that device was deactivated.
On your My Office Account page, you may have deactivated this device so you could install Office on a different computer.
Or maybe you deactivated the wrong device by mistake.
So, to continue working you will need to reactivate Office.
You don’t need the original product key but instead you just sign in to the Microsoft Account you use for Office 365.
Select Sign in.
Enter the email address and then the password for your Microsoft Account.
As long as you still have an active subscription and available installs, Office will be reactivated.
That’s it. Now you can get back to work.