"Activate Windows" watermark randomly popped up after years of Windows 10 use

Hi NovaStorm32

My name is Andre Da Costa; an Independent Consultant, Windows Insider MVP and Windows & Devices for IT MVP. I'm here to help you with your problem.

Open Start, type: CMD

Right click CMD

Click Run as administrator

At the prompt, type: slmgr.vbs /dlv

Hit Enter

Take a screenshot of the resulting dialog then post in a reply here.

Learn how:

https://answers.microsoft.com/en-us/windows/wik...

If you have a retail license, you can contact support to reactivate it.

https://partner.support.services.microsoft.com/...

You can also call support:

https://support.microsoft.com/en-us/help/13948/...

Well, you are running a retail license.

Click Start > Settings > Update & security > Activation > Troubleshoot

See if the troubleshoot resolves or determine what is the cause of the problem.

Because you have a retail license installed, you should be able to contact support to reactivate.

https://partner.support.services.microsoft.com/...

You can also call support:

https://support.microsoft.com/en-us/help/13948/...

This is what pops up, hope it'll shed some light onto what's going on

The PC was built for me as a surprise birthday gift, and the Windows was activated with a key before I actually got it -- Though the key was genuine. My father (The one who built it) doesn't know where the key/code is, if he still has it at all.

This is what the Activation settings window is saying -- you can see I've customized the theme and colour before, so this PC has been activated until recently.

Hi Nova. I'm Greg, an installation specialist and 9 year Windows MVP here to help you.

How was Windows 10 originally Activated on the PC? Did it come preinstalled from Factory, was it Upgraded with free or paid Upgrade, or was it a retail copy and license?

For Upgrade, when you first upgraded and it activated it assigned a permanent Digital License to the PC in Microsoft Activation Servers so you can reinstall any time and in any way you want as long as you reinstall the licensed version. It should reactivate soon after going online. More about Digital LIcenses vs. Product Keys here:

https://support.microsoft.com/en-us/help/12440/...

You can move the Digital License to new hardware following this procedure: https://support.microsoft.com/en-us/help/20530/...

Factory installs have the Product Key embedded in BIOS or UEFI firmware and should activate themselves, but you can check for the key by installing ProducKey and look for the OEM-BIOS key: http://www.nirsoft.net/utils/produkey-x64.zip

Retail keys must be reinserted for reinstalls during install or in Settings.

What is the Status and Edition shown at the top of the page at Settings > Update & Security > Activation?

Run the Activation Troubleshooter at Settings > Update & Security > Activation. If it says you have a Digital License then no matter what method above only the Generic Version Key can be inserted to reactivate: http://winaero.com/blog/generic-key-to-install-...

If this fails you can contact Microsoft Support: https://partner.support.services.microsoft.com/...

I hope this helps. Feel free to ask back any questions and keep me posted. If you'll wait to rate whether my post helped you, I will keep working with you until it's resolved.

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