How to Activate Windows 11

To activate Windows 11, open Settings > System > Activation. Use Change product key for a valid 25-character key, or connect online if this PC already has a digital license for the installed edition. Signing in with a Microsoft account does not create a license. If you are trying to clear an Activate Windows watermark, start here to resolve the activation problem.

This guide covers Windows 11 Home and Pro on a PC you own. It shows how to check your status, activate with a product key or a digital license, reactivate after a hardware change or reinstall, and fix common errors. Steps follow Microsoft Support, checked in October 2026. Volume-licensed work and school PCs are activated by the organization, so ask your IT department instead.

Check Whether Windows 11 Is Already Activated

1. Press Windows key + I to open Settings. Result: the Settings app opens; select System if another page appears.
2. Select System > Activation. Result: the Activation page shows your edition (Home or Pro) and your activation status.
3. Read the status message. Result: you’ll see one of the four messages below.

• Windows is activated: you’re activated, but your Microsoft account isn’t linked.
• Windows is activated with a digital license: you’re activated, and the license isn’t linked to your Microsoft account yet.
• Windows is activated with a digital license linked to your Microsoft account: your account is linked, which can help with reactivation after a hardware change.
• Windows is not activated: you’ll see an error explaining why. Keep reading.

These messages come from Microsoft’s Activate Windows help page.

Which Activation Method Do You Need?

Microsoft uses two methods. A digital license lets you activate without entering a product key. A product key is a 25-character code in the format XXXXX-XXXXX-XXXXX-XXXXX-XXXXX. Which one you have depends on how you got Windows:

• Eligible upgrade from an activated Windows 10 PC: digital license for the same edition. Microsoft’s Windows 11 upgrade page describes current eligibility.
• Bought Windows 11, or a Pro upgrade, in the Microsoft Store app: digital license, tied to the account in the confirmation email.
• PC that came with Windows 11: its key can be preinstalled on the device, included with the packaging, or supplied on a Certificate of Authenticity (COA). Many PCs activate automatically.
• Boxed or digital copy from a retailer: product key, on a label in the box or in the confirmation email or retailer’s digital locker.
• Refurbished PC: product key, which the refurbisher, not Microsoft, must provide.

Activate Windows 11 With a Product Key

1. Connect the PC to the internet. Result: Windows can reach Microsoft’s activation servers.
2. Open Settings > System > Activation. Result: the Activation page opens.
3. Select Change next to Change product key. If you don’t see it, expand Upgrade your edition of Windows first. Result: a box for the key opens.
4. Type the 25-character key. Result: the Next button becomes available.
5. Select Next, then Activate if asked. Result: if Microsoft accepts the license, the status becomes active. Expand Activation state to check the details. If an error appears, use the troubleshooting section.

Your key is usually in the store’s confirmation email, on a card in the box, or on a COA label. Microsoft only keeps a record of keys bought from its online store, which you can check in your Microsoft account’s order history. To read a key that’s already on your PC, see how to find your Windows 11 product key.

The key has to match your edition. Microsoft notes that, for example, an Enterprise key can’t activate Home or Pro. If you’re moving from Home to Pro, see how to get Windows 11 Pro.

Activate Windows 11 Without a Product Key: Use a Digital License

This method requires an existing digital license for this PC and the same edition, Home or Pro. If no valid license exists, connecting online or creating an account will not activate Windows; use a licensed key or the Store purchase option below.

1. Connect to the internet. Result: Windows can check this hardware’s digital license. No key entry is needed for the licensed edition on the same device.
2. Sign in to Windows with the Microsoft account that holds the license, if you have one. Result: Windows can match the license to your account.
3. Check Settings > System > Activation. Result: check for an active status and expand its details. If Windows is still not activated, note the error code and follow the troubleshooting section.

Link the license to your Microsoft account

Microsoft calls this step essential, because it’s what lets you reactivate after a hardware change. Do it while Windows is still activated.

1. Go to Settings > Accounts > Your info and confirm you see Administrator under your name and an email address above it. Result: you know you’re on an administrator account that uses a Microsoft account.
2. Go back to System > Activation and select Add an account. Result: a Microsoft sign-in window opens.
3. Sign in. Result: the status changes to “Windows is activated with a digital license linked to your Microsoft account.”

Check the full status message to confirm whether the account is linked. A missing Add an account button alone is not proof.

Reactivate After a Hardware Change

Windows ties your license to your hardware. After a big change, such as a new motherboard, Windows may no longer find a matching license. Keep the same edition, Home or Pro, and link your account before the change when possible. Microsoft’s hardware change guide describes two routes; reactivation is not guaranteed for every license or hardware change.

If you have a digital license

1. Sign in as an administrator and connect to the internet. Result: the troubleshooter can reach Microsoft.
2. Go to Settings > System > Activation > Troubleshoot. This option only appears when Windows isn’t activated. Result: the troubleshooter reports that Windows can’t be activated.
3. Select I changed hardware on this device recently, then Next. Result: you’re asked to sign in.
4. Sign in with the Microsoft account linked to the license. Result: a list of devices on that account appears.
5. Check This is the device I’m using right now next to your PC, then select Activate. Result: check whether Windows reactivates. If it fails, note the error and contact Microsoft or the PC maker.

If you used a product key

Enter the same key under Settings > System > Activation > Change product key. Microsoft notes that if Windows came preinstalled and you replaced the motherboard yourself, you may need to buy a new license. If the PC maker replaced it, Windows should reactivate automatically.

Activate After Reinstalling Windows 11

Before reinstalling, back up your files and confirm your license and edition. If this PC has a digital license, reinstall the same edition on the same device and choose I don’t have a product key when setup asks. Windows activates online after installation. If you use a product key, enter it during setup or afterward with Change product key. Before you reinstall, confirm Windows is activated and the license is linked to your account.

Other Ways to Activate

• Command Prompt: an administrator can install a key with slmgr. See how to activate Windows 11 with Command Prompt.
• Offline PC: follow the Installation ID and Confirmation ID process below. The PC being activated can stay offline, but another device needs internet access to Microsoft’s portal.
• Buy a license: on the Activation page, select Go to Store (or Open Store) to buy a digital license from Microsoft.

Not sure you need to pay? See how to get Windows 11 legally without buying a product key.

If the PC Cannot Activate Online

Microsoft’s current offline activation guide uses its Product Activation Portal. It says to use the portal instead of calling a phone number displayed by Windows. A valid license is still required.

1. Open Settings > System > Activation. On supported newer builds, choose Automated Help to display the Installation ID. Older builds can show Activate by Phone and a region selector instead.
2. On another connected device, follow the Product Activation Portal link in Microsoft’s guide. Sign in, select Windows 11, and submit the Installation ID to request a Confirmation ID.
3. Return to the activation screen, choose Enter Confirmation ID, enter the returned ID, and select Activate Windows. Check the resulting status.

If those controls are missing or the request fails, Microsoft’s guide includes command-line alternatives and support options. SLUI 4 may be unavailable on newer Windows 11 builds.

Troubleshooting Activation Errors

For general Windows 11 activation failures, start with the Run the troubleshooter in Get Help option in Microsoft’s activation errors guide. For hardware changes, the Activation > Troubleshoot route above remains documented. Record the code and check it again after troubleshooting, since it can change. Common ones:

• 0xC004C003: the key isn’t valid, often because it was already used on another device. Contact the seller, or use a key unique to your PC.
• 0x803F7001: Windows couldn’t find a valid license. Enter a key with Change product key or buy one with Go to Store.
• 0xC004F211 or 0xC004F213: the hardware changed or no key was found. Use the hardware change steps above.
• 0xC004F212, 0xC004E016 or 0xC004F210: the key is for a different edition. Install the edition you’re licensed for, or use a matching key.
• 0xC004FC03: you’re offline or a firewall is blocking activation. Check the connection and ask IT about network restrictions on a managed PC. For an offline PC, use the current portal process above.

Avoid cheap keys from unknown sellers and “activator” downloads. Microsoft marks keys used on too many devices as invalid, and activator tools from random sites are a common way to get malware.

Resolve the Activate Windows Watermark

Read the exact desktop message before changing settings. For Activate Windows, check Settings > System > Activation, use the matching digital license or key, and confirm an active status. Then check whether the reminder clears. If your existing license has stopped activating, troubleshoot before buying another license. Contact the seller or manufacturer if a newly purchased PC arrived with an invalid key.

Wallpaper changes, logon-message policies, and editing version-display settings do not provide an activation license. This guide does not promise a permanent removal through those workarounds. If Activation already says active but the message persists, record the exact message and contact Microsoft support.

Test Mode is a different watermark. Microsoft’s test-signing documentation explains that it relates to loading test-signed drivers. The TESTSIGNING boot option is not a Windows activation method. Do not change boot settings to address an activation reminder.

Frequently Asked Questions

Does signing in create a free Windows license?

No. A Microsoft account can link an existing digital license and help with reactivation. It does not replace the license requirement.

Do I need a key after a clean install?

Not if the PC already had a digital license for the same edition. Choose I don’t have a product key during setup.

Can I move my license to a new PC?

It depends on the license. Microsoft says a preinstalled license may not survive a motherboard replacement, and that you may need to buy a new one. For a retail key, check the license terms that came with it.

Why is Troubleshoot missing?

Microsoft says the Activation troubleshooter only appears when Windows isn’t activated.

Finish by checking both the installed edition and the activation status. If activation still fails, use the exact error code and your purchase or device details when contacting the appropriate support team.