Microsoft has said that devices running unsupported versions of Windows will no longer receive security updates after next year's Windows Update certificate rotation. The certificate rotation is a routine security measure, but it will also serve as a cutoff for older systems that are no longer supported.
The change means that anyone still on an outdated Windows version will miss future security patches once the rotation takes effect. Microsoft's statement points to the need to move to a supported version of Windows to continue getting updates.
The exact list of affected versions is not part of the announcement, but the warning covers any device on an unsupported release. For users and organizations, the practical takeaway is to upgrade before the rotation to avoid losing security protection.