Windows 10: "activate windows" watermark appearing suddenly; had genuine Windows 8, got free upgrade to...

Like the title says, I bought my laptop several years ago with Windows 8 installed on it. At some point, Microsoft "upgraded" me to Windows 10. Now, after a system update, I am getting the "Activate Windows" watermark. I run the troubleshooter and it says I need to buy genuine copy, which seems incorrect as I had a genuine Windows 8 copy when I bought my laptop. I do not have a product key for my original Windows 8 it came pre-installed, I don't see a sticker with the code anywhere on the laptop either.

:)

 

Windows 7 not genuine problem

It seems like that's an OEM windows copy, it will do that the every time you reinstall the OS. If you have the key, next time you see the "not genuine windows copy" click it and choose to activate by phone, everything else is pretty straight forward as it explains step-by-step. If it doesn't work, then its highly likely that you got a Pirate copy.

 

Activate Windows watermark suddenly appeared

No changes have been made to the hardware, and I've had this laptop for nearly two years. This morning, a watermark appeared in the bottom right corner of my screen telling me to activate windows.

On the activation page in settings it tells me I don't have a valid digital license or product key, with the error code "0xc004f012".

It also suggests that I try the troubleshooter below, which then tells me that troubleshooting was interrupted and gives the error code "0xc3f6501".

 

Legally download Windows 7 and 8

I have a product key that is genuine, is this a retail key? I got it free from my university's dreamspark. If so, I could do a clean install with an upgrade disc (provided at microsoft's site) without any extra steps such as registry editing, etc etc.. ?