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Windows 10 Phone Activation

Windows 10 logo

Sometimes online activation cannot be performed immediately. This can have many causes. Often it is due to overloaded activation servers, or a used license. We will show you how you can still easily activate Windows within 2 minutes.

You can skip steps 1 – 4 if you have already entered the key during online activation.

Step 1

Open Settings using the key combination Windows + i.

Keyboard

Step 2

Click on Update & Security.
Screenshot of the Windows settings menu highlighting the 'Update & Security' option at the bottom left.

Step 3

Click on Activation in the vertical menu on the left.
Screenshot of Windows settings highlighting the 'Activation' option in the 'Update & Security' menu. The 'Delivery Optimization' section is open on the right.

Step 4

Now enter your license key and then click on Next.
Screenshot of the activation window in Windows settings. The field for entering the Product Key is highlighted, as well as the 'Next' and 'Cancel' buttons

Step 5 (Phone Activation)

Did you receive error code 0xC004C008, or do you not want to connect your device to the internet? No problem – you can also simply activate your operating system by phone. If you receive a different error code, please contact us at [email protected]. Close the displayed error message and click on Activate by phone on the previous page.

If the option for phone activation is not displayed, enter the command SLUI.EXE 4 into the desktop search bar instead.

Screenshot of Windows settings in the 'Activation' area. The notice 'Windows is not activated' and the option 'Activate by phone' are highlighted

Step 6

Select your preferred language and region.
Screenshot of the Windows selection screen for country or region with Germany as the selected option. 'Next' and 'Cancel' buttons are visible at the bottom.

Step 7

Now the Installation ID and a toll-free number to call will be displayed. You will be connected to a virtual assistant from Microsoft. Below you will find the call process.

Note: Microsoft does not accept calls with a blocked caller ID!

Microsoft Call Process

  1. May the call be recorded?
    Press 1 for Yes, or 2 for No.
  2. You will receive an individual security code. Enter this using your phone’s keypad.
  3. Press 1 to activate Windows.
  4. Press 1 to activate Windows 10 or 11.
  5. Press 1 to confirm the installation has already taken place.
  6. Press 1 to confirm an error code.
  7. Press 1 to confirm a reactivation.
  8. Press 3 to confirm error code 0xC004C008.
  9. Press 1 to confirm you are at the affected PC.
  10. Now you will be asked to enter the Installation ID via your phone’s keypad.
  11. Important: When asked how many times you have already activated the product, press 0 !
  12. If you have entered the Installation ID correctly, you will receive the Confirmation ID for the final activation in return.
  13. Note down this Confirmation ID carefully!
  14. Then click on Enter Confirmation ID in the Windows window.

Screenshot of the Windows activation screen prompting to enter the Installation ID. The Installation ID fields and the 'Enter Confirmation ID' button are highlighted.

Step 8

Now enter your Confirmation ID into blocks A-H and confirm your entry by clicking Activate Windows. Done!
A Windows 10 activation screen prompting the user to enter a confirmation ID for Phone Activation, with eight input boxes labeled A to H, and Activate Windows and Cancel buttons at the bottom.