No product key can be changed for Windows.
No product key can be changed for Windows.
You should start fresh by reinstalling everything on your system. The ISO you downloaded for Home is not compatible with Pro, so you’ll need to use the original installation for Pro. The key comes from your motherboard, not from the ISO file.
When you reinstall Windows 10, it might automatically activate using the motherboard ID. The no-key shouldn’t alter this process, so the installation should remain consistent.
It didn't work with Pro or Home; they both requested a product key each time.
Consider setting up the operating system included with the device.
It appears now with Windows 10, though it likely debuted on Windows 8.1 Pro. Reinstall and then upgrade to Windows 10 would help. If problems persist, contact Microsoft support and describe the issue—they should assist. The Microsoft customer portal is generally reliable.