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Error code 0xc004c008

Windows Activation Error 0xC004C008 – Product key already in use?

Did you receive error code 0xC004C008 or the message “The product key has already been used” when activating Windows or Microsoft Office? Don’t worry—we’ll show you how to solve the problem quickly!

Select your software and follow our step-by-step activation guide:

Activate Microsoft Windows 10 by Phone
Activate Microsoft Windows 11 by Phone
Activate Microsoft Office

Read the guide now and activate Windows in just a few seconds!