Activation error

0xC004C004

Product key can't be used to activate Windows

Windows did not accept the product key for activation. Microsoft explains 0xC004C004 only in a table row it shares with other activation codes, so the advice here stays close to that row.

Symptoms

Windows displays 0xC004C004 when you activate with a product key
Settings > System > Activation still shows that Windows is not activated

Causes

The product key you entered can't be used to activate Windows.
After an upgrade to Windows 11, the activation servers were busy.
Windows 11 is not activated after a reinstall that followed the free upgrade offer. Microsoft says it should activate automatically unless the device had a significant hardware change, such as a new motherboard.

How to fix it

Collect your key details

Your key is in your order email and under My Library in your Lizensa account. Note its last five characters and the edition shown under Settings > System > Activation (Windows 10: Settings > Update & Security > Activation). Never send the full key.

Wait if you have just upgraded

If you upgraded from an activated Windows 7 or Windows 8.1 while the activation servers were busy, Microsoft says Windows 11 will activate automatically. You can also wait a while and then select Activate on the same page.

Ask us before trying another key

Microsoft's general advice for this group is to enter a different key. With a key from Lizensa, contact our support instead and let us check it.

Why this page is short

We found no Microsoft article dedicated to 0xC004C004. Microsoft's activation error table puts it in one row with 0xC004C001, 0xC004C007, 0xC004F005, 0xC004F050 and others. We list only the reasons from that row.

When you write to us, we also need to know which edition is installed. Which Windows is installed? shows where to see it, and Your key and your edition explains which key fits which edition. For Windows 10, see Does your key fit the installed edition?.

When to contact Lizensa support

Contact our support when the key from your order fails with this code. Give us your order number, the last five characters of the key, the edition shown in Settings and the exact message or a screenshot. Our support is available Monday to Friday, 09:00 to 17:00 CET.

Still need help?

If error 0xC004C004 keeps blocking activation after these steps, our support team can check your key and license channel directly.

Contact support

Genuine licenses

Genuine licenses that activate cleanly

Windows 11 Home

€24.90

Windows 11 Pro

€29.90

From the blog

Microsoft Office 2024 LTSC: The Last One-Time Purchase Office Suite?

Microsoft Office 2024 LTSC is the latest perpetual Office suite — but with Microsoft 365 dominating, is this the last standalone version?

6 min read

Is It Legal to Buy Cheap Software License Keys? What You Need to Know

Wondering if cheap software keys are legal? We explain the difference between legitimate wholesale licenses and grey-market keys, and how to stay safe.

9 min read

Where to Buy the Cheapest Microsoft Office 2024 License (Legitimately)

Find the best deals on genuine Microsoft Office 2024 licenses. Compare editions, pricing, and where to buy safely at the lowest price.

7 min read