The company said Windows 7 users could upgrade to Windows 10 on their existing hardware, and obtain a full licence, if the hardware met certain requirements.
But the company said it would be better to move to a new PC with Windows 10 in order to take advantage of new hardware capabilities in the latest version of its operating system.
Unless a user's existing hardware fails, he or she can continue to use Windows 7 after 14 January 2020, Microsoft said, but there would be no security and feature updates.
However, support for Internet Explorer on Windows 7 devices would be discontinued a year from yesterday.
Users who want to obtain support and updates after the cut-off date will have to pay, with the sum to be paid increasing each year up to three years after which the support would end.