Back in July 2015 when Microsoft launched Windows 10, the new operating system was offered completely free of charge to anyone with Windows 7 and 8.1 who performed the upgrade and activated the install in the first 12 months.

And while the free upgrade offer ended in July 2016, Microsoft still allowed users with assistive technologies to upgrade to Windows 10 at no extra charge in case they were running accessibility features in Windows 7 or 8.1.

The more interesting tidbit is that this particular method of upgrading to Windows 10 at no cost included absolutely no checks on users’ computers, so even if no accessibility features were enabled, the free of charge upgrade was still allowed to go through.

This offer was supposed to end shortly after the July 2016 deadline for the original free upgrade promo, but for some reason, Microsoft decided to keep it up and running for a lot longer, turning it into more of a loophole to get Windows 10 at no charge.

The clock is ticking

Earlier this year, however, Microsoft finally announced that it would be closing this loophole on December 31, so this is pretty much your last chance to upgrade to Windows 10 at no cost.

“If you use assistive technologies, you can upgrade to Windows 10 at no cost as Microsoft continues our efforts to improve the Windows 10 experience for people who use these technologies. Please take advantage of this offer before it expires on December 31, 2017,” Microsoft said.

It goes without saying that whoever wanted to upgrade to Windows 10 should have done this by now, but given that no other way to get the operating system at no charge is known at this point, users who are still on Windows 7 and 8.1 should think twice if they want to skip this offer or not.

For what it’s worth, Windows 10 can be purchased from the Microsoft Store in the United States for $119.99 if you choose the Home SKU or for $199.99 if you go for the Pro version.