Reinstall MS Office 2016

Office 2016 is a one-time purchase that is licensed for one install, but it can be transferred to a new computer that belongs to the same owner if the old one was replaced or failed.

For Office 2016, the product key is typically redeemed once, then the license is tied to a Microsoft account. After that, installation and activation are done by signing in, not by re-entering the product key. The shorter key format being rejected suggests that the key has already been redeemed and the correct way to reinstall is via the associated account.

To reinstall Office 2016 on the new laptop without using Office 365:

1. Go to https://account.microsoft.com/services and sign in with the Microsoft account that was originally used to redeem/activate Office 2016.
2. Under “Services & subscriptions,” locate the Office 2016 (for example, Office Home & Student 2016, Office Home & Business 2016, or Office Professional 2016) entry.
3. Select the Install option shown for that Office 2016 product. This downloads the Office 2016 installer.
4. Run the downloaded setup file. If prompted by User Account Control, allow the app to make changes.
5. When installation completes, start an Office app (such as Word) and, if prompted, sign in with the same Microsoft account to activate. Do not enter the old product key again.

If Office 2016 was obtained through the Microsoft Workplace Discount Program or as a volume license, the installation steps may differ and might require using the Workplace Discount Program order history or contacting the organization’s IT department.

References:

• Download and install or reinstall Office 2021, Office 2019, or Office 2016
• “This product key has already been used” error in Office
• Install or reinstall Office or Microsoft 365 through Microsoft Workplace Discount Program
• Troubleshoot installing Office
• Office is no longer on your PC after you do a Recovery in Windows
• Move my Home and Student 2016 to a new computer - Microsoft Q&A