First, sorry if this is posted somewhere else, but doing a few searches, I couldn't find it, so I decided to make this thread. So you bought a PC/Tablet with Windows 8 (not 8.1) preinstalled and found out that if you ever need to reinstall Windows (hard drive upgrade/hard drive failure/major virus) that you can't just install Windows 8.1, but have to install Windows 8 then upgrade to 8.1 through the store and then install all the updates. Well, NO MORE! This simple process allows you to install the latest Windows 8.1 on your machine and activate it as a clean install. NOTE: This does NOT work to upgrade an existing Windows 8 install to Windows 8.1. That still requires the Windows Store install as far as I know. FIRST Before you go wiping out your machine, you need to figure out the OEM key that is used in your preinstalled copy of Windows 8. There are several utilities for doing this, including SIW (find an older free one), ProduKey, Magic Jellybean, etc. Once you find your Windows 8 OEM Key, save it somewhere or write it down for use later. SECOND Once your have your key backed up, go ahead and make a USB install stick for Windows 8.1 using the latest ISO (en_windows_8.1_with_update_x64_dvd_4065090.iso as of this writing.) Use the tool Rufus (rufus.akeo.ie) to make the USB install stick. (Insert 4GB+ USB drive, open Rufus, select USB drive under Device, click CD drive icon near bottom and select Windows ISO, then select the GPT UEFI option under Partition Scheme and then click Start.) THIRD (The important step) When the drive is created, open notepad and copy and paste the following: Code: [EditionID] [Channel] OEM [VL] 0 Save this file as ei.cfg inside the 'sources' directory on your USB installer. This is the trick to getting Windows to take your OEM key. By default it installs as an RTM copy, not OEM, so this file forces it into OEM mode and lets you install Windows 8.1 without a key. FOURTH Eject the USB drive you created and boot your computer off it. When asked which version of Windows to install, select the appropriate version your computer came with (if unsure, select Core, not Professional) and skip entering the product key. We will get to this later. Finish installing Windows as you normally would. FIFTH (and final) Once Windows is installed and boot, skip entering the product key in the initial setup, then continue to setup Windows as you normally would. Once the machine is fully booted, go to PC Settings and activate Windows, and when it asks for a Product Key, put in the key you saved in step 1 (your Windows 8 OEM key) and it should connect to the internet and successfully activate. Hopefully this works for you. I tried this on 2 separate machines a handful of times to check that it worked and it did. I really wish Windows 8.1 and Windows 8 keys were the same so we wouldn't have to find ways around it, but at least there is a solution. Enjoy your fresh, updated install!