I have a Windows machine (laptop) that needs fixing. The current installation is really badly broken (e.g. the taskbar is unresponsive, but the Explorer windows work, booting takes literally half an hour) and when I try to access the settings app and click on the tile to access the reset settings it instantly crashes. The same happens in Safe Mode.

I have created a USB install medium using the tool offered by Windows on my own Windows desktop machine. I've ensured that both the laptop and the USB tool have the same version of Windows (Home, 64-bit, NL). When I want to reinstall Windows on the laptop with this stick I am asked to enter a serial number which I obviously don't have. I don't want to try and see if I can phone activate it, because if it fails the install is gone.

I need to reinstall this Windows machine from a USB stick. There are a few problems I can't find an immediate solution for on the Windows pages.

  1. If I use a tool such as ProduKey to extract the serial number, will this work?
  2. If the above does not work, how can I reinstall this Windows machine?
  • Your laptop OS is OEM? – vembutech Nov 22 '16 at 10:36
  • Yes. It's a Sony Vaio laptop and it shipped with (I think) Windows 7. At this point it has been upgraded to Windows 10 (free upgrade program). – Christophe De Troyer Nov 22 '16 at 10:39
  • I don't see any problem on using ProduKey. If you have a license for your Windows, you'll have a legit product key – sysfiend Nov 22 '16 at 10:39
  • The reason I'm asking that is because I have found plenty of cases where it did not work out. I guess I'll give that a shot then. – Christophe De Troyer Nov 22 '16 at 10:42
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    Why are you extracting the license key, since your using Windows 10, you don't actually ever need it to install Windows 10 – Ramhound Nov 22 '16 at 12:58

If you utilized ProduKey to determine the machine's local product key, it would simply find the generic, post-upgrade key and that won't actually work. In reality, your activation on that device is a digital license. As a result, when/if you need to perform a full wipe and reload on that machine, you can skip the screens that request a product key input and it will still automatically activate. Here is a good reference from Microsoft themselves:

Activation in Windows 10

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You may have noted that since Windows 8 there are no more (ugly and hard to remove) Windows stickers (containing keys) on laptops. This is because nowadays the BIOS firmware may contain "Microsoft Software Licensing Tables" named SLIC and MSDM that contain your key. It is quite easy to extract the Windows key of the Windows installation that came with your computer. Boot Ubuntu Live from a USB stick, open the terminal and run:

sudo cat /sys/firmware/acpi/tables/MSDM

You will find your key at the end of the "file".


  • 1
    Very interesting! Thanks for letting us all know as an answer! – Christophe De Troyer Apr 22 at 9:15

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