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I have seen this question answered for Windows 7, but I am wondering if the same holds true for Windows 8.1--I recently installed a legal copy of Win 8.1 on a machine I built and I now want to use that machine with Linux and install my copy of Win 8.1 on a new build.

Is this possible? Thanks!

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You can indeed do this but only if you have a full retail non-OEM version of Windows 8.1. You also might have to activate by phone. – Ramhound Dec 30 '13 at 18:34

According to Microsoft you can uninstall the license key on the first computer, this frees the license up in Microsoft's servers, and then install it on the second machine. If you're not able to run the command to uninstall the license key on the first computer then you can call in, explain the situation, and they'll issue a new license key.

Of course, all of this assumes that you are using a full license and not an upgrade.

If don't want to format the old machine, then its best you just uninstall the license just in case you decide to go back to it.

Press Windows key + X

Click Command Prompt (Admin)

At the command prompt, type: slmgr.vbs -upk

Hit Enter, this will uninstall the product key from the computer and set it back to trial mode, you are now free to use it on another computer.


Once you have transferred to the new machine, you might need to reactivate by telephone:

  1. Press Windows key + X then clickRun, then type: slui.exe 4

  2. Next press the 'ENTER' key

  3. Select your 'Country' from the list.

  4. Choose the 'Phone Activation' option.

  5. Stay on the phone (do not select/press any options) and wait for a person to help you with activation.

  6. Explain your problem clearly to the support person.

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ALL Windows 8 Retail licenses are considered to be non-upgrade FULL licenses. Microsoft discontinued the Upgrade System Builder license model with Windows 8.1. Any Windows 8.1 you purchase yourself from Microsoft or any non-OEM partner would be considered to be a FULL System Builder license. In other words unless the license came installed on an OEM computer it can be used on multiple computers provided the license is first uninstalled from the previous computer. I am sure there is a limit to how many uninstallation/activation Microsoft will allow of course. – Ramhound Dec 30 '13 at 18:45
System Builder is the term Microsoft uses to describe a non-OEM system provider ( i.e. the guy down the street who built and sold you a computer ) within the terms of service for the System Builder license it outlines your rights and what part Microsoft has ( i.e. Microsoft is under no obligation to provide you phone support on Windows thats left up to the person who built your system ). Please understand this is a very rough and brief explaination of the System Builder license. – Ramhound Dec 30 '13 at 18:50
Thanks @Ramhound, I missed the license changes Microsoft made with Windows 8. – LeoB Dec 30 '13 at 18:55
What I describe is only valid with Windows 8.1. Windows 8 still had Upgrade and System Builder ( i.e. Full ) licenses. One could upgrade a previous version of Windows the other technically could not. – Ramhound Dec 30 '13 at 19:09

protected by Community Sep 4 '15 at 23:47

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