Microsoft ended mainstream support for Windows 8.1 on January 9, 2018, and will be ending extended support on January 10, 2023. This means that Microsoft will no longer provide security updates or technical support for the operating system. It is important to note that this only applies to Windows 8.1 and its various editions. If you are using Windows 8.1, it is recommended to upgrade to a newer version of Windows, such as Windows 10 and 11, to continue receiving security updates and support. It is generally a good idea to keep your operating system up to date to ensure that you have the latest security and feature updates.