How to Fix Windows Activation Error 0xC004C008

If you’re getting error 0xC004C008, please try to activate Windows by phone by following the instructions below:

1. Press Windows + R to open the Run box.
2. Type SLUI 4 and press Enter to open the phone activation wizard.
3. Select your country or region, then click Next.
4. Call the toll-free number shown on screen and follow the automated prompts. You will be asked for the Installation ID displayed in the wizard.
5. The system will give you a Confirmation ID. Enter it in the wizard and click Activate Windows.
6. Activation is complete once the confirmation ID is accepted.

Still getting error 0xC004C008?

If phone activation does not resolve the error, confirm you are using the correct edition for your key (a Pro key will not activate a Home or “N” edition installation). Make sure your system date, time, and region are correct, then restart and try SLUI 4 again.

If you purchased your key from Bitcodes and still cannot activate, contact our support team with your order number and a screenshot of the error so we can check your key and provide a replacement if needed. You can find genuine, transferable license keys on our store.

Frequently asked questions

Does phone activation with SLUI 4 always fix 0xC004C008?

Phone activation resolves most cases of 0xC004C008 because it completes activation through a separate channel from the online server. If the key has genuinely exceeded its activation limit, you may need a replacement key.

Is error 0xC004C008 the same on Windows 10 and Windows 11?

Yes. The error has the same meaning and the same phone-activation fix on both Windows 10 and Windows 11.