Every Windows 10 operating system that's Installed and activated on the computer, has what's called a Product Key, that Is either pre-Installed by the manufacturer, or added by the end user when formatting their PC. In order to have a fully-functional OS, It must contain a valid Product Key. Whilst there are many tools that can extract It from the operating system, In this tutorial, I will show you how to manually decode the Product Key.
Before I begin, I'd like to make one thing clear. You may come across a Product Key and a Product ID. They are NOT the same. The former Is used to activate the operating system, and the latter Is used to Identify the Windows version you're currently running. So how do you know the difference between the two? Simply stated, a Product Key consists of 25 characters, In the format as per the above Image. A Product ID Is usually 20 characters.
If you've lost your Windows 10 Product Key and want to reinstall the OS, I will demonstrate how to manually decode It from the Windows Registry. Sure, there are many tools that do the work for you, but In the event you cannot boot your PC (to run a given tool), accessing the Registry In an offline state Is your best option.
It's beyond the scope of this article to document how to access the Windows Registry offline, hence I will be working within the Windows environment. In a nutshell, you will learn how to decode the entry In the Registry, Into a 25 character Product Key. So without further delay, let's rip Into this tutorial.
The first thing you need to do, Is access the Windows Registry. Open the Run menu, enter regedit and hit OK.
The Windows Registry Editor will now open, so navigate to the following directory.
Then on the right pane, double click on DigitalProductId, as arrowed below.
Now In the Value data field, you will see a bunch binary values that mean absolutely nothing to us as humans. This Is the actual data, that will be decoded Into a Product Key.
To start the process, It must be saved as a Registry file. To do this, right-click the CurrentVersion key, and then select Export.
Navigate to a directory of your choice, and give the file a name. For the purpose of this guide, I've named mine Product Key. In the Save as type, select Registration Files (*.reg) and also click the Selected branch radio button. When done, hit Save.
Open the folder where you saved the above Registry file, right-click It and select Edit as shown below.
Notepad will now open by default. If It doesn't, select It. Now we need to find the DigitalProductId entry, so rather than manually looking for It, click on the Edit tab and then hit Find.
In the Find what Input field, enter DigitalProductId and hit Find Next. As you can see, the entry has been found.
Now select everything after DigitalProductId, as shown below by using the copy & paste function. It must start at "DigitalProductId" and stop just before "DigitalProductId4". This Is what will be decoded Into the 25 character Product Key.
To decode It, we'll use a freeware tool named Windows Product Key Finder, which can be downloaded here. Execute the tool, and then hit Decode DigitalProductId.
Paste the contents that you copied In Step Nine above, Into the text field, and then hit Parse DigitalProductId. As you can see, the Windows 25 character Product Key has been returned In plain text. This Is my result, so obviously I've edited the Image. A job well done Indeed.
Although there are so many tools that retrieve the Windows Product Key within a few seconds, you cannot always rely on software to do the work for you. As mentioned at the beginning of this tutorial, If you can't boot Into the Windows environment to execute a given tool, then the methodology above must be performed In an offline state. In other words, boot with a Live CD/USB such as Emergency Boot Kit, and access the Windows Registry thereafter.
Alternatively, for whatever reason, you can obviously apply this tutorial whilst you're navigating within the Windows operating system.