Free Windows 10 upgrade still available, but you need to be quick

Back when Windows 10 first launched, Microsoft made a huge push to get those on Windows 7 and 8.1 to upgrade. Most notably, this included a promotion that offered Windows 10 upgrades for free for a year, along with the sometimes infuriating desktop pop-ups that came with it. That promotion ended some time ago, but as it turns out, there’s …