Starting with version 1.32.0 (planned for public release on April 10th), Plex Media Server will no longer support versions of Windows older than Windows 10 (version 1607) or macOS older than 10.13 (High Sierra).
While older versions of the Server may continue to run in these now-unsupported environments for the time being, we encourage everyone to upgrade their systems to at least Windows 10 (version 1607) or macOS 10.13 (High Sierra) to ensure that both your operating system and Plex Media Server continue to receive critical security and feature improvements moving forward.
It has been pointed out to us that the minimum versions we still support are versions that the vendor themselves no longer support.
We recommend that users run Plex Media Server and Plex apps on operating system versions that are supported by their respective vendors in order to maintain the highest levels of security and functionality. We recognize that some users may need to stay on older operating system versions due to lack of hardware support or for other reasons. We try to provide support for those users to the greatest extent that’s reasonably practicable, even if the vendor has stopped their support. However, making use of modern platform features and development tools sometimes makes it infeasible to continue to support for all older versions. We have chosen to support versions that allow us to continue developing Plex Media Server while keeping the number of impacted users to a minimum.