Learn how to activate Windows using a product key or digital license, check your activation status, and link your Microsoft account.

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 product key from a new product key card.

A Windows product key is a 25-character code used to activate Windows. It looks like this: Locate your product key for Windows 10 or Windows 11. Depending on how you got your copy of Windows 10 or Windows 11, you'll need either a 25-character product key or a digital license to activate it.

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.

Office Home & Business, Office Home & Student, and Office Professional can be installed on a single computer. 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 ...

When you select the option to activate Office by telephone, you may see the following error: Telephone activation is no longer supported for your product. Note: This issue impacts Office non-subscribers only—those who purchased the product as a one-time purchase.

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.

Product activation is an anti-piracy technology that is designed to verify that the product is legitimately licensed. When you activate your product, no personal information is sent to Microsoft. Who needs to activate their copy of Office?

If you keep getting prompted to activate Office Standard or Office Professional Plus on a new PC, you can update the registry to stop the prompts.

Make sure that the edition, Windows 11 Home or Windows 11 Pro, is the same before and after your hardware change. Your digital license and product key will reactivate only if the edition remains the same. You can see your edition on the same Activation page where you checked your activation status.