Over the years the Windows Certificate of Authority (COA) or Product Key has taken many forms. The most common of which are the physical sticker on the system, which up until Windows 10 was by far the most common type, however, this has been superseded by a system called OEM Activation 3.0 (OA3) which is most commonly referred to in the industry as 'injection', where a Product key is digitally injected to the motherboard's firmware and cross-checked with Microsoft's Cloud Activation servers. It is a really clever system that has solved a huge number of issues with the old physical keys method, however, it is not quite flawless.

Windows 10

On most modern Windows 10 systems, your product key is typically no longer required. On >99.9% of the systems we sell, the keys are injected and registered to the motherboard firmware during our production process and then we submit that data to Microsoft's Activation Servers where the activation record is stored in the cloud. Therefore, under normal circumstances, you will never need to find this information. Windows can see this key, even when you're reinstalling Windows, so it's likely you'll never need to check it.

There is always that <0.1% though so very occasionally we have shipped systems with Windows 10 with COA stickers, as shown below in the Windows 7 / 8.x section below, so in some situations you may need to manually check your system physically to find the code.

'Valid Digital License' Error [0xC004C003]

Sometimes a system doesn't automatically activate or it says it can't activate Windows on this device. It should automatically activate during the Out of Box Experience (OOBE) as you agree to the Microsoft Terms & Conditions. However, the Microsoft Activation Servers sometimes seem to play up and activation doesn't always happen automatically on a new or sometimes even a reinstalled system. In Microsoft's infinite wisdon, when this happens, you often get an error message saying your Windows License isn't valid (what's with the drama?).

In the most recent instance of this type of thing occurring, you will typically see the key quoted on the screen will likely have the following characters shown:

Windows 10 Home - FC2HD

Windows 10 Pro - WFG6P

These are 'staging' or 'default' keys to Enable automated activation. Further information about this process can be seen here and here, if you're interested. A full article describing the most recent issue can be found here. Our Windows images will be updated to include the fix ASAP.

Fortunately, there is a really simple fix so if you can please try these steps first before contacting us for further assistance it's very likely to resolve your problems. Typically, in these situations, all you need to do is click the Change Product Key text and type in the injected key (called the OEM Key) from your system in the box that pops up.


You can find the OEM Key using this software: ShowKeyPlus and for more info about the tool and for an alternative .zip version, click here. Simply install and run the tool to see your key.


The OEM Key is the one you want to use, not the Installed Key (as this is the staging key described above that will not work). Simply type the OEM Key into the prompt and go through the dialogue to activate and it will typically activate within a few seconds to a minute.

[Based upon user feedback, we've started to include a simplified process for the above]

  1. Open Settings
  2. Click on Update & security
  3. Click on Activation
  4. Click the Change product key link
  5. Type the 25-digit OEM Key from the ShowKeyPlus software into this box
  6. Click Next to complete the process and the system should activate

If the above method doesn't work, we have sometimes had to use a more forceful approach to override this default key so if the above doesn't work, please try the Advanced Fix below.

Advanced Fix

If the above doesn't work, you sometimes need to launch CMD (Command Prompt) as an Administrator and run this command:


Press Enter and wait for the confirmation prompt. After that, reboot the PC.

(The X characters represent your product key, so replace them with the OEM Key characters from the ShowKeyPlus software)

If you check the Activation screen after this, it should say that you're activated.

If all else fails, you may need to do a Telephone Activation.

Telephone Activation


Windows 7 / 8.x

When you first turn on your PC you'll be asked to fill in some basic information to help setup Windows. If you do not have a key in the motherboard firmware itself or you are reinstalling Windows 7 or 8.x, one of these setup screens asks for the Windows product key (sometimes referred to as license or COA key). Assuming you ordered your computer with Windows included you will find a small sticker (examples shown below) on the computer tower itself, normally on the right hand side panel towards the very rear on desktop tower systems and typically on the underside of a laptop.

This sticker tells you which version of Windows you ordered and also includes the 25 character product key. You'll need to type this in exactly so that your Windows license can be verified.