Microsoft’s plan to end Windows 10 support on October 14 has sparked a last-minute legal challenge from a user determined to keep the popular operating system alive.

Lawrence Klein, who owns two laptops running Windows 10, has filed a lawsuit arguing that Microsoft should continue providing critical and security updates free of charge. The company currently offers an Extended Security Update (ESU) program priced at $30 per device which will keep security patches flowing until October 13, 2026.

According to Forbes, the case could impact as many as 700 million Windows 10 users worldwide. While Microsoft first announced the end date in 2021 before Windows 11 was released many users are reluctant or unable to upgrade, often due to cost or the newer OS’s stricter hardware requirements.

The lawsuit also notes that the retirement of Windows 10 will push some users to purchase entirely new computers. Devices built for the 2015-era OS may not meet the technical specifications for Windows 11, forcing owners to choose between paid extended support or a hardware upgrade.

For Microsoft, the 10-year lifecycle of Windows 10 aligns with its standard support policy. The company argues that advances in security, performance, and features make moving to newer platforms essential.

Still, a significant portion of users have held on. Analysts point to several factors slowing Windows 11 adoption including the cost of upgrading, reluctance to change, and compatibility concerns.

In the meantime, those unwilling to switch can secure two more years of security updates via the ESU program, redeem Microsoft Rewards points, or sync eligible settings all of which extend coverage until late 2026. Whether Klein’s lawsuit can delay or alter Microsoft’s plans remains to be seen.