Hi

I bought a PC a year back. I want to geninstaler windows 8.1 on it. When it says it is missing some files in Settings. My problem is just that I can not find the product key for windows. It was bought with windows 8 on.  I did not receive a CD with the purchase, but is it possible to do it via USB and how? it is most important to find the product key

from GM

Hi,

Did you want to update to Windows 8.1 from Windows 8?

You could refer to this article to get it:

Update to Windows 8.1 from Windows 8

http://windows.microsoft.com/en-in/windows-8/update-from-windows-8-tutorial

In addition, please run sfc /scannow command to repair missing or corrupted system file firstly:

Use the System File Checker tool to repair missing or corrupted system files

http://support.microsoft.com/kb/929833

About product key, you need contact your manufacturer to obtain it.

If I understand you correctly, you have a system which came preinstalled with Windows 8, but without a physical product key (sticker), and you would like to install Windows 8.1 onto this system. In some cases, manufacturers have made use of firmware embedded product keys as are described in this Microsoft Support article: KB 2796988. If your system is one such system, installation of the proper media will automatically detect the applicable key. This will require that if the system originally came installed with Windows 8, you use Windows 8 media to install, then use the Windows Store to update to Windows 8.1.

If your system does not contain a firmware embedded product key, or if you are unsure, it would be recommended to contact the system manufacturer. If you do not have the installation media intended for the system, you may also need to request installation media from the manufacturer.

Brandon
Windows Outreach Team- IT Pro
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