How to Activate Windows 10 Enterprise or LTSC

1. Open the Windows 10 activation page

Open Settings from the Start menu, select Update & Security, and then choose Activation.

The Activation page shows the installed edition and current activation status.

2. Enter the Windows product key

Select Change product key. If the option is unavailable, confirm that your Windows account has administrator permissions.

Enter the 25-character key exactly as supplied, select Next, and allow Windows to verify it.

3. Review the activation result

If the activation page shows Windows is activated, the license was accepted and no telephone activation is required.

If Windows shows error 0xC004C020, error 0xC004C008, or another online activation message, continue with telephone activation. This can be required for Enterprise or LTSC licenses and does not automatically mean the key is invalid.

4. Open telephone activation with slui 4

Press Windows + R to open the Run window. Type slui 4 and select OK. Windows will open the telephone activation wizard.

5. Copy the Installation ID

Select your country or region and continue. The wizard displays an Installation ID (IID) divided into groups. Copy every group exactly as shown.

6. Get your Confirmation ID

Use one of these methods to exchange the Installation ID for a Confirmation ID (CID):

1. Microsoft Product Activation Portal: the official, free option. It is manual: sign in, choose product activation, select Windows, and enter the IID groups.
2. InstantLicX Telegram bot: a faster paid option. Send the IID to the Telegram bot as text or as an image.
3. GetCID.xyz: a paid web service that accepts the IID as text or image and also supports API, WordPress, WhatsApp, and Telegram integrations.

Using the free Microsoft portal

Open the Microsoft Product Activation Portal, sign in with a Microsoft account such as Outlook or Hotmail, and choose Activate a Microsoft Product.

Select Windows, choose the Windows version that matches your installation, and continue until the portal requests the Installation ID.

Paste the complete Installation ID, verify the groups, and submit it.

If the portal asks how many computers have been installed with this copy and this is a new activation, enter 0.

7. Enter the Confirmation ID

After the IID is accepted, the selected method returns a Confirmation ID divided into groups.

Return to the Windows activation wizard and enter each CID group into its corresponding field. Select Activate Windows to finish.

8. Confirm Windows 10 activation

Return to Settings > Update & Security > Activation. The activation status should now confirm that Windows is activated.

Troubleshooting

• Confirm that the installed Windows edition is Enterprise or LTSC.
• Install pending Windows updates and restart the computer before trying again.
• If Windows shows 0xC004C020, continue with telephone activation instead of replacing the license immediately.
• Review every IID and CID group for missing or transposed digits.