How to fetch Product Key of Windows 7/8.1/10 if COA is not available

Windows product keys are very important to keep because if we reinstall Windows or change the hardware of the machine, we would need to re-activate Windows and it requires the product key of Windows. Without the product key, you won't be able to activate Windows. Although Windows 10 activation is now digitally linked with Microsoft account but still, after changing the hardware, you might face issues with the activation of your Windows OS. So here are a few steps which you can follow to fetch the product key of the Windows operating system from the installed machine.

1. Using Command Prompt
To fetch the product key using the command prompt, you may open cmd as admin and run the following command:

wmic path softwarelicensingservice get OA3xOriginalProductKey

Remember that this command can fetch the product key only if you are using an OEM machine which came pre-installed with Windows and the key was injected in the Motherboard of the machine.

2. Using PowerShell

To fetch the product key using the PowerShell, you may open PowerShell as admin and run the following command:

powershell "(Get-WmiObject -query ‘select * from SoftwareLicensingService’).OA3xOriginalProductKey"

Remember that this command can fetch the product key only if you are using an OEM machine which came pre-installed with Windows and the key was injected in the Motherboard of the machine.

3. Using VB Script

To fetch the product key using the VB Script, you may copy and paste the following code in a notepad file and save it as keyfinder.vbs and then run the file. It would show the product key in a small pop-up:

Set WshShell = CreateObject("WScript.Shell")
MsgBox ConvertToKey(WshShell.RegRead("HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\DigitalProductId"))

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

This command can fetch product key from OEM and non OEM PCs both.

4. Using the ProduKey tool
If none of the above methods work, you may use the NirSoft ProduKey tool to fetch the product key of your Windows. This tool can fetch the keys of Windows and MS Office also. Just download the tool from this link and run it as admin in your PC and it would show the product keys installed in your machine.