Activate a brand new Office product key. Troubleshoot activation errors. Activate Microsoft 365 or a non-subscription version of Office. When you start an Microsoft 365 app that's not activated, you'll be prompted to sign in to Microsoft 365.

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.

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

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.

Activate Microsoft 365 or a non-subscription version of Office. Activate Office that's pre-installed on a new Windows device. Activate an Office purchase or offer that's included on a new Windows device. Activate Office from Microsoft Workplace Discount Program. Activate a brand new Office product key.

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?

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 ...

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.

Activation helps verify that your copy of Windows is genuine and hasn’t been used on more devices than the Microsoft Software License Terms allow. This article will help you troubleshoot and fix common activation errors in Windows. For help finding your product key, see Find your Windows product key.

If you're unable to activate Windows 10, the Activation troubleshooter could help. To use the troubleshooter, select Start > Settings > Update & Security > Activation , and then select Troubleshoot .