Description Find your Windows product key with ShowKeyPlus. • If you bought Windows from an authorized retailer, the product key will only show as the Installed key. This applies to OEM System Builder keys as well. • If you upgraded Windows, the Original key will be the key installed prior to the upgrade. NB if you upgrade to Windows 10 Youhad Windows 8 PRO. You get Windows 8.1 PRO for free. Depending on how Windows 8 was originally put on the machine (legitimately, of course) would determine whether you have a product key you can copy on paper and put in a safe place or if it is embedded in the system BIOS. So, if you had Windows 8 PRO and it was a legitimately licensed copy Step1: Click on the Windows 10 download page link here. Step 2: Click 'Download Tool Now' - this downloads the Windows 10 Media Creation Tool. So, Step 3: When finished, open the download and accept the license terms. Step 4: Choose: 'Upgrade This PC now' then click 'Next.'. SelectStart > Settings > Update & Security > Activation. Under Activate Windows Now section, select Activate by Phone. Select your location (or the location nearest to you) Enter your Windows 8.1 product key, select Next, and follow the instructions. To activate Windows 8.1 by phone: NjgHZ.