Looking to reinstall Windows on the same PC or move your copy of Windows from an older PC to a new one? Well, depending on what version of Windows you have installed, you may or may not need the product key.
If you have Windows 7 or earlier, your system is activated by a single product key that is stored in the Windows registry. Using third-party software or a simple script, you can extract this key quite easily. You can then use this key to install Windows again on the same machine or use it to install Windows on another machine as long as you first deactivate the key on the original machine.
If you have Windows 8.1 installed, you won’t have any product key unless you bought a retail version of the operating system. Otherwise, the product key is now stored in an encrypted format in the BIOS or UEFI firmware. This means a lot of Windows 8 machines bought from Dell, HP, etc. won’t even have a COA sticker on the side or back of the machine.
This is good and bad. It’s good because you can reinstall Windows and not have to worry about any product key. It will simply activate automatically since the key is stored in the BIOS or firmware. It’s bad because it doesn’t allow you to use the key on another machine if something happens to the first one.
Also, if you have to replace certain parts in your machine, it might cause Windows to deactivate. In this case where it’s the same PC, just with different parts, you can call Microsoft and they will activate it for you.
With Windows 10, everything changes again. Now there is no product key at all! Windows 10 introduces something new called a digital entitlement. This entitlement is based on off your computer’s hardware and is stored with Microsoft. This is true for any OEM machines or PCs that were upgraded to Windows 10 from Windows 7 or Windows 8. This means you can’t transfer your copy of Windows 10 to another computer. It also means your original Windows 7 or 8 product key will disappear.
If you buy a retail copy of Windows 10, however, you will get a product key, and the license can be transferred over to another PC. Now there is one exception to the above rules: if you upgraded Windows 7 or 8 to Windows 10, then you can technically transfer Windows 10 to another computer until July 29th, 2016. On this date, Windows 10 is no longer going to be free and there will be no more free upgrades.
So you can technically install Windows 7 or 8 again on a different PC and then upgrade it to Windows 10 again. It’s definitely a lot of work, but possible. If you’re thinking about upgrading Windows 7 or 8 to Windows 10, you should first use this post to find your product key and store it somewhere safely in case you need to reinstall Windows 7 or 8. Read my previous post on Windows 7, 8, and 10 licensing.
Note that you can also use the methods below to show your product key on Windows 10, but it’s just going to give you a generic key, not a real product key.
Find Windows Product Key – ProduKey
The first method to get your product key on Windows 8 and earlier is by using a third-party program from Nirsoft called ProduKey. It’s free and Nirsoft software is always clean, so you don’t have to worry about viruses or malware.
Scroll down towards the bottom of the page to get to the download links. If you have 64-bit Windows installed, download the x64 version of the program. Once you download it, unzip the files and run the ProduKey application.
It will instantly find all Microsoft applications installed on your system and give you the Product ID and Product Key. It’s a great program and you can just delete the program files once you are done. I also like using this program because I’ve ended up writing down the product keys for other products like Office that I hadn’t thought of looking up.
Find Windows Product Key – Script
If you don’t want to download any software, you can simply create a script that will return the value of the product key. In order to create the script, you need to first open Notepad. Then, copy and paste in the following code:
Set WshShell = CreateObject("WScript.Shell") MsgBox ConvertToKey(WshShell.RegRead("HKLMSOFTWAREMicrosoftWindows NTCurrentVersionDigitalProductId"))
Function ConvertToKey(Key) Const KeyOffset = 52 i = 28 Chars = "BCDFGHJKMPQRTVWXY2346789" Do Cur = 0 x = 14 Do Cur = Cur * 256 Cur = Key(x + KeyOffset) + Cur Key(x + KeyOffset) = (Cur 24) And 255 Cur = Cur Mod 24 x = x -1 Loop While x >= 0 i = i -1 KeyOutput = Mid(Chars, Cur + 1, 1) & KeyOutput If (((29 - i) Mod 6) = 0) And (i <> -1) Then i = i -1 KeyOutput = "-" & KeyOutput End If Loop While i >= 0 ConvertToKey = KeyOutput End Function
Now click File and then Save As. To save the file as a script, you need to add .vbs to the end of the file name and you need to choose All Files for the Save as type box.
Click Save and now go to the folder where you saved the script. Double-click to run it and you should get a small window with your Windows product key.
This script is short and doesn’t give you any other info about Windows. If you need to know what edition of Windows you have installed, just open the Control Panel and click on System. At the top, it’ll tell you the edition.
So those are two easy ways to get your product key for Windows. As mentioned earlier, Windows 10 no longer has a product key, so it’s a good idea to get your key before you upgrade Windows 7 or 8. If you’ve already upgraded your machine, you should be able to reinstall Windows 10 (the same edition) on that machine without needing to reactivate or enter any product key.
If you replace too many parts on your computer or your computer dies and you want to move it to another computer, you can either reinstall Windows 7 or 8 before July 29, 2016 and upgrade or you will have to call Microsoft and hopefully they’ll allow you to activate Windows. If you have any questions, feel free to comment. Enjoy!