Activation error

0xC004F050

Product key is not valid

You entered a product key that cannot be used to activate Windows. The key may be mistyped, intended for a different product or channel, or genuinely invalid. Microsoft's activation-error page lists 0xC004F050 as the "key can't be used" family together with 0xC004F034.

Symptoms

Error: "You entered a product key that can't be used to activate Windows. Enter a different valid Windows product key or buy a new product key"
The key is rejected immediately at entry, not at activation time
The same key may have worked on another device

Causes

The key is mistyped — characters O/0, I/1, and 5/S are easy to confuse
The key belongs to a different product or edition than the one being activated
The key is counterfeit, expired, or was never issued by Microsoft

How to fix it

Re-enter the key carefully

In Settings > System > Activation > Change product key, retype the 25-character key. Product keys never contain the letters O, I, L, or U — if yours does, it was mistyped or misread.

Match the key to the product

Confirm the key is a Windows key for the installed edition, not an Office/other-product key, and not for a different Windows edition.

Buy a valid license

If the key came from an unverifiable source, Microsoft's guidance is to buy a genuine license from the Microsoft Store and enter that key instead.

Check for upgrade-path issues

If you upgraded from Windows 7/8.1 or reinstalled after the free-upgrade window, activation servers may need the device to retry. Select Activate and try again, then run the troubleshooter.

Still need help?

If error 0xC004F050 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

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