I am running Windows 7 and when offered the free upgrade to Windows 10 some years ago, I tried it, but then needed to back off because of problems that developed after the upgrade. I would like to attempt it again, but would like the free upgrade. How do I go about getting this done on both a laptop and a desktop unit that I own. One is a Lenovo T530 (laptop) and the other is a Lenovo IdeaCentre B5 series (desktop). Thank you.