Windows 8 Pro Upgrade Product Key can't be used to activate Windows after a clean install

TheEricChau asked on

Hi guys,


I purchased a Windows 8 Pro Upgrade and received the Product Key that I have used to download and perform a clean install of my laptop using a USB Flash Drive (format my HD then install). But now in my brand new installed Windows 8, I can't use that Product Key to activate Windows as it says that the key is only for an Upgrade, not a clean install. I wasn't aware of this problem when I did the clean install. So how can I activate my Windows now?

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Ben Herila replied on

It!s an UPGRADE, so you need to UPGRADE your existing system. Clean installation isn't supported. Sorry.

That is simply not true.


If you had a hardware problem and you need to re-install Windows 8, you can do so by using the installation media that the wizard prompted you to create (or installation media that you ordered, if you chose to order discs).


If you don't have installation media, you can re-install your old version of Windows and run the upgrade again.


Either way, you will need the product key that you received when you paid for Windows 8. If you choose to do a clean install of Windows 8 from the installation media, then you will also need to call Customer Service for help activating your copy of Windows.



Ben Herila

Program Manager | Windows Server

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BinaryInk replied on
The work around for this, while probably not officially supported for obvious reasons (they want more money), is to change a registry key. This was posted for Windows 7 update keys doing the same thing on a forum (though I had an update version AND did a clean install MULTIPLE times without having to do this) but worked without an issue on my laptop running Windows 8 regardless.

1. Run the registry editor (regedit)
2. Find the following key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Setup\OOBE
3. Change the value for 'MediaBootInstall' from 1 to 0
4. Open an elevated command prompt (run as admin)
5. Run the following command: slmgr -rearm
6. Reboot

If you already entered your key, check the activation: for me it was already activated and I needed to do nothing more. If not, type in activate windows and type in the key; it should work. Also, do yourself a favor and export this key from regedit and save it somewhere if you ever are required to do another clean install. I know I did.

I had the same issue here, and it's simply asinine. Have the INSTALLER check for a copy of Windows 7 or lower on a hard disk before INSTALLING Windows 8; that way, we can have a clean install LIKE IT LETS US DO. Either that, or remove the option altogether. Most importantly: inform your customers of this limitation (because telling them that they can do a clean install using update media, while true, is VERY misleading when the product license won't allow it).

In short, it's bull-poo (I wanted to use a word that rhymes with 'trap' but obviously that's too vulgar. Enjoy "bull-poo" because what it implies is actually worse) like this that leads to pirating. If I hadn't found the registry edit, I had 3 options as I saw it:

1. Uninstall Win8, reinstall Win7, upgrade Win7 to Win8 (makes a lot of sense, right? Especially seeing that I didn't know my key wasn't activated until hours after entering it, and had already installed drivers and software) 
2. Buy a 'full' Win8 product key (There's an extra couple bucks that I didn't need...)
or 3. Pirate it

Hint: I was leaning towards 3. I already paid, I had every right to use the software I just purchased without having to jump through hoops or repurchase Win8 for both my PCs (not to mention, I own so many Microsoft products: from some of their mice to their phone to an Xbox...). 

(I'm in no way endorsing pirating, just saying simply that this is generally the root cause--aside from pricing--and it's time that companies begin to realize that. Restrictive DRM generally leads to more frustration from your customers and more pirating results. Period. Rather than muddying the legal waters through lobbying, take preventive action and serve your customers...)  
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