🔑 Activate Microsoft Windows 10/11 Using Byphone Key (No Internet Required)
To enter/change your product key in Windows 10/11, follow the illustration below.
📷 View exampleAfter entering the activation key, you will see the following error: 0xC004C008 or 0xC004C020.
📷 View example1. Press ❖ Win+R to open Run, then type: SLUI 4, and press OK. (Make sure there's a space between SLUI and 4).
📷 View example2. In the Location section, choose your country and click Next.
📷 View example3. Write down the numbers in Installation ID: 1 2 3 4 5 6 7 8 9.
📷 View example4. Go to Active & Getcid, enter the number into Step 2 - Installation ID (IID) and click GET.
📷 View example5. Enter the received Confirmation ID (CID) into the corresponding boxes, then click Activate Windows.
📷 View example6. Activation successful.
📷 View example