Updating windows product key
It is getting difficult to download anything from Microsoft without a valid serial number.
Changing product key in Windows 8 has been a big headache to the users as there is no direct procedure or application for the same. Well, command prompt and tools does it all for you.
If the end user skips this during OOBE, the user will be reminded later to enter a valid product key.If Windows 8 came preinstalled on your computer, your product key should be on a sticker on your computer or with your documentation. Fortunately, if you can't find documentation of your Windows 8 product key, you may be able to extract it from the Windows Registry using a program called a .It's a quick process that takes less than 15 minutes.When you upgrade to Windows 10 from an older Windows version (one that lets you upgrade for free), you rely on the operating system’s old (and authentic) product key to carry you through the upgrade.
After that upgrade, that key is not upgraded itself so that it will work on Windows 10 clean installs.
Next, create a Windows 10 installation disc or USB stick and run it on your system.