On July 31st Microsoft stopped allowing users of windows 7 & Windows 8 to upgrade for FREE to Windows 10, however there seems to a workaround.

If you tell Microsoft that you intend to use Windows 10 on Assistive Technologies, you can still get the free upgrade offer even after the general public deadline expires as Microsoft continues our efforts to improve the Windows 10 experience for people who use these technology.

To avail of this just follow this link Windows 10 free upgrade

This tip was found on ZDnet** At the time of writing this works **