By Adam Smart, Ecokeys Support Engineer — Last updated 26 July 2026

How to Check Whether Windows 11 Is Activated

1. Select Start.
2. Open Settings.
3. Select System.
4. Select Activation.

The Activation page shows:

• The installed Windows edition, such as Windows 11 Home or Windows 11 Pro
• The current activation state
• Whether activation uses a digital licence
• Options to change the product key or run the troubleshooter

How to Activate Windows 11 with a Product Key

A Windows product key contains 25 characters in this format:

XXXXX-XXXXX-XXXXX-XXXXX-XXXXX

To activate Windows 11 after installation:

1. Connect the PC to the internet.
2. Open Settings > System > Activation.
3. Next to Change product key, select Change.
4. Enter the valid 25-character key.
5. Select Next.
6. Follow the on-screen instructions.
7. Return to the Activation page and confirm that Windows reports as activated.

If activation fails, record the exact error code before trying other fixes. The error code often reveals whether the problem is an edition mismatch, a key issue, a hardware change or a temporary connection problem.

How Windows 11 Digital Licence Activation Works

A digital licence is an activation entitlement associated with the device hardware. It may also be linked to a Microsoft account.

Windows can activate automatically with a digital licence when:

• The same Windows edition was previously activated on the PC.
• Windows is reinstalled on the same device.
• The device is connected to the internet.
• The licence still matches the hardware and edition.

To check whether the licence is linked to a Microsoft account, open Settings > System > Activation and expand the activation status information.

Activate Windows 11 During Installation

Windows Setup may ask for a product key during installation.

1. Enter the valid product key when prompted.
2. Make sure Windows Setup selects or installs the edition that matches the key.
3. Complete the installation.
4. Connect the PC to the internet.
5. Open Settings > System > Activation to confirm activation.

When reinstalling Windows on a PC that already has a digital licence, you can often select I don’t have a product key during Setup. Install the same edition that was previously activated, and Windows should attempt automatic activation after connecting to the internet.

How to Activate Windows 11 Home

Windows 11 Home uses the same main activation route:

1. Open Settings > System > Activation.
2. Select Change product key.
3. Enter the Windows 11 Home key.
4. Complete the online activation prompts.

When Windows 11 Home came preinstalled on the PC, activation may be automatic through a digital licence or a product key stored in the device firmware.

Windows 11 Home key not working

Check that the Activation page actually shows Windows 11 Home. A Home key cannot activate Windows 11 Pro.

Also check:

• The key was entered without extra spaces.
• The PC has a working internet connection.
• The date, time and time zone are correct.
• The key has not already been used beyond its licence terms.
• The key is intended for Windows 11 Home rather than another edition.

How to Activate Windows 11 Pro

If Windows 11 Pro is already installed:

1. Open Settings > System > Activation.
2. Select Change product key.
3. Enter the valid Windows 11 Pro key.
4. Select Next and complete activation.

A Windows 11 Pro key will not directly activate an installation that still shows Windows 11 Home. In that situation, complete the Home-to-Pro edition upgrade first.

How to Upgrade Windows 11 Home to Pro

An activated Windows 11 Home installation can normally be upgraded to Windows 11 Pro without reinstalling Windows.

1. Confirm that Windows 11 Home is activated.
2. Open Settings > System > Activation.
3. Select or expand Upgrade your edition of Windows.
4. Next to Change product key, select Change.
5. Enter the valid Windows 11 Pro product key.
6. Select Next.
7. Allow Windows to complete the edition upgrade and restart when requested.
8. Return to Activation settings and confirm that the edition is Windows 11 Pro and that it is activated.

Your files and installed applications should remain in place during a normal edition upgrade, but make a current backup before changing Windows.

Activating Windows 11 After Reinstallation

Windows 11 should normally reactivate after a reinstall when:

• The same PC was previously activated.
• The same edition is installed again.
• The device has not undergone a major hardware change.
• The PC is connected to the internet.

During Setup, choose the same edition that was previously activated. After installation, open Settings > System > Activation and allow Windows time to contact the activation service.

If automatic activation does not occur, enter the original product key or use the Activation troubleshooter.

Reactivating Windows 11 After a Hardware Change

A significant hardware change, particularly replacing the motherboard, can stop Windows from finding the digital licence associated with the device.

Before a planned hardware change, link the digital licence to a Microsoft account where possible.

After the hardware change:

1. Connect the PC to the internet.
2. Sign in with the Microsoft account previously linked to the licence.
3. Open Settings > System > Activation.
4. Select Troubleshoot.
5. Select the option indicating that hardware was changed recently, when available.
6. Choose the relevant device and follow the prompts.

The Windows edition must be the same before and after the hardware change. Transfer and reactivation also depend on the type of licence and whether it is eligible to move to different hardware.

Activate Windows 11 Using Command Prompt

Advanced users can install a valid key and request activation using Microsoft’s built-in licensing commands. For the full command-line process, see our Windows 11 Activation CMD guide.

The standard commands are:

slmgr.vbs /ipk XXXXX-XXXXX-XXXXX-XXXXX-XXXXX
slmgr.vbs /ato
slmgr.vbs /xpr

Use only your own valid product key or an authorised organisational activation method. Avoid public KMS servers, unknown batch files and scripts claiming to activate Windows without a legitimate licence.

Windows 11 Activation Troubleshooting

1. Check the Windows edition

Open Settings > System > Activation. Confirm that Home or Pro matches the licence purchased.

2. Check the product key carefully

Enter all 25 characters exactly. Avoid spaces before or after the key.

3. Check the internet connection

Normal online activation requires Windows to contact Microsoft’s activation service.

4. Correct the date and time

Open Settings > Time & language > Date & time and enable automatic time settings where appropriate.

5. Restart Windows

A restart can complete an edition change or refresh activation components after a key has been entered.

6. Run the Activation troubleshooter

Open Settings > System > Activation and select Troubleshoot when the option is displayed.

7. Record the exact error code

Do not repeatedly enter the key without checking the message. Common codes can identify an invalid key, wrong edition, KMS configuration, hardware change or activation-server issue.

8. Check for a hardware change

Use the hardware-change troubleshooting route when the device was previously activated but stopped activating after a major component was replaced.

9. Check whether the key is already in use

A one-PC licence cannot normally remain activated on multiple PCs at the same time. Remove it from the previous device where transfer is permitted.

For a detailed diagnosis, see our Windows product key not working guide.

Common Windows 11 Activation Error Codes

Does Windows 11 Need to Be Activated?

Windows may install and operate before activation, but activation confirms that the installed edition has a valid licence. An unactivated installation can display activation reminders and restrict certain personalisation options.

Activation does not replace security updates, antivirus protection, backups or correct licensing. It confirms that Windows accepted the relevant product key or digital entitlement for the device and edition.

Where to Find a Windows 11 Product Key

Depending on how Windows was obtained, the product key may be:

• In the purchase confirmation email
• Inside the retailer’s account or order information
• On a Certificate of Authenticity supplied with eligible hardware
• Stored in the firmware of a device that came with Windows
• Provided by an employer or organisation for a managed device

Do not share a full product key in public screenshots, support forums or social-media posts.

Frequently Asked Questions