You can use the troubleshooting tool to understand what's going wrong with the system:
Windows 10 product key not working
The way to go about this is Upgrade your Windows 7 or Windows 8.1 to Windows 10. Ensure that it is activated and then if you wish, clean install Windows 10 on the same device. If you directly clean installed Windows 10 and then used your earlier key, it will not work.
If there is a problem with your product key, then you can re-enter a genuine key to activate, you can go to some online stores such as Amazon, e shell to buy, of course, think of genuine and cheap must go to Vanskeys.com
Cannot activate Windows 10
If you upgraded to Windows 10 for free from Windows 7 SP1 or Windows 8.1 Update, and ended up with a non-activated Windows 10, try this:
Open Settings app > Update & security > Activation. Select Go to Store, and check if a valid license is available for your device. If a license isn’t available, you’ll need to buy Windows from the Store. This post will show you how to check Windows 10 activation status, activate it, or change the product key.
Windows 10 Product Key blocked
If Windows 10 blocks your product key, even after upgrading first & then clean installing, then we have a few suggestions to make:
- Uninstall the product key. Then enter the product key anew and try again. Use another key and see.
- Rebuild the Tokens.dat file. The Tokens.dat file in the Windows operating system is a digitally signed file, which stores most of the Windows activation files. Sometimes the Tokens.dat file may get corrupted as a result of which Windows Activation may not take place successfully.
- Open an elevated CMD and run Dism /Online /Cleanup-Image /RestoreHealth to repair the system image. Then try again.
- Activate Windows 10 by Phone.