If your purchase of Office or Microsoft 365 came with a product key, you enter your product key on one of the websites listed below for your product. After you enter your key, you can download and install Office, or you can renew your Microsoft 365 subscription.

To use Microsoft 365 on your new device, you can activate Microsoft 365 as a 1-month trial of Microsoft 365 Family. You can also buy Microsoft 365 or a non-subscription version of Office, add Microsoft 365 to an existing Microsoft 365 subscription, or enter a …

If Office is prompting you for a product key, and you want to buy a product key to activate Office, it's better to uninstall your current version of Office and then buy and install a new version of Office from the Microsoft Store.

Get help with product key errors, or geographical region errors, when you redeem a new Office product key on Office.com/setup.

How to change your product key to fix activation errors that can occur if you own and install multiple one-time purchases of Office..

If Office activation fails, you'll see Unlicensed Product or Non-commercial use / Unlicensed Product in the title bar of your Office apps, and most features of Office are disabled. To restore all features of Office, you'll need to fix the problem that's causing activation to fail.

An activation code (also known as an activation key) is used to activate the software after installation. Activation ensures that the software is genuine and legally licensed. Unlike a product key, which is entered during installation, the activation code is applied after installation.

For Microsoft 365 and Office 2021 - Download and install or reinstall Microsoft 365 or Office 2021 on a PC or Mac. For Office 2019, 2016 or 2013 - Download and install or reinstall Office 2019, Office 2016, or Office 2013 .

Many tasks for Office products don't require a product key because your Microsoft account takes care of them instead. Using product keys with Office

If you try to install and activate these versions of Office on a different computer (owned by you or someone else), or on the same computer after a hardware change, you might see an error message that says you've reached the maximum number of activations.