As we reported yesterday, a new Windows 10 issue showed up out of nowhere, causing systems running Microsoft’s latest operating system, regardless of the version, to no longer be activated.
The number of users believed to be impacted is likely huge considering how many posts made the rounds in the last 24 hours, but despite this, Microsoft has provided very little details on what exactly happened and what caused the problems.
In short, here’s what happened. Users running Windows 10 Pro were suddenly alerted that their copy of Windows wasn’t activated, despite them using a genuine license for the operating system.
Trying to resolve the issue manually and perform another activation failed. Needless to say, rebooting didn’t help, and some even tried to clean-install Windows 10, obviously with no success when it comes to the activation process.
The most awkward issue was that some users ended up being told they are running Windows 10 Home and not Pro, so it appeared that the bug somehow downgraded their version of Windows. Trying to upgrade to Pro from the Microsoft Store failed as well.
Microsoft has remained tight-lipped at first, and information on the issue made the rounds mostly through unofficial channels. But in a recent statement, a Microsoft engineer explains that both Windows 10 Pro and Enterprise are affected, so we assume that those running Windows 10 Home are on the safe side for now. Here’s the statement in full:
“We are aware of reports that some customers’ Windows 10 Pro and Windows 10 Enterprise machines are not recognizing their licenses as activated.
Users may receive the following notification: “Error: you are running Windows 10 Pro, but you have valid digital license for Windows 10 Home," or one of the following error codes 0X803F8001, 0xC004C003. We are actively working to resolve this within 24 hours. You can still use your PC; however, the watermark will appear until activation is restored. Thank you for your patience. We will update this post with additional information as needed and once activations are restored.”
Microsoft hasn’t offered a fix, but as it turns out, the activation troubleshooter embedded into Windows 10 actually helps at this point. Note that the troubleshooter didn’t resolve the bug at first, so it’s believed that the company managed to find the cause of the glitch, so the troubleshooter has been updated with the solution. Oddly enough, Microsoft hasn’t confirmed this, leaving users impacted by the bug to continue looking for a resolution.
To reactive Windows using the built-in troubleshooter, launch the Settings app from the Start menu and navigate to the following path:
Settings > Update & Security > Activation
Launch the troubleshooter and wait for the scan to complete. If everything works correctly, Windows should find your digital license and reactivate. As an alternative, you can also click the Change product key option and enter your license once again – while we’ve heard this method works in some cases, it’s not guaranteed it’d do the same for all users.
Also, you can try forcing the activation from an elevated Command Prompt. To do this, launch the Start menu, type cmd.exe, right-click the result > Run as administrator, and type the following command:
slmgr.vbs -ipk product-key
Replace the product-key tag with your own Windows license and then press enter. If the process works, your copy of Windows should now be activated.
We’re still waiting for a full fix from Microsoft and obviously for some extra details to let us know what exactly happened and caused this bug, but in the meantime, you can use the steps highlighted here to reactive Windows.