For the general public, Microsoft ended the free upgrade offer for Windows 10 on July 29, 2016. However there are ways to get a free upgrade from Windows 7 SP1 or Windows 8.1.
Upgrade for people using assistive technologies
First of all, Microsoft has announced in May 2016 in a blog post that the free upgrade will be continued after July 29, 2016 to people who use assistive technologies. All those people need to do: Go to this Microsoft page and follow the steps mentioned on that page. The button Upgrade now visible on this page downloads the Windows10Upgrade24074.exe tool.
After launching the tool, a wizard will guide users through the upgrade process – and the tool won't check, whether people are in need of using assistive technologies. So all users how has missed the dead line July 29, 2016 (due to technical problems finishing the upgrade) are able to participate in a free upgrade.
Upgrade using Media Creation tool
Microsoft has removed Get Windows 10 app (GWX) from Windows 7 SP1 and Windows 8.1. But users are able to download Windows Media Creation Tool and download a copy of Windows 10 installation media and burn the ISO to a DVD or store the install files on a bootable USB stick. Or it's possible to download a copy of Windows 10 iso via Microsoft's Techbench program. Burn the ISO image to a DVD or use a tool like Rufus to create a bootable USB stick.
There has been also some reports that Microsoft still accepts installing Windows 10 as an upgrade from Windows 7 SP1 or Windows 8.1 or accepting a clean install and using the Windows 7/Windows 8.1 key for activation. Only OEM keys seems to be blocked. So give it a try.
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