Users of systems with processors without SSE2, such as the Pentium III, are no longer eligible for Windows 7 patches, even though official support will run until January 14, 2020.
The end of support is evident from security article KB4088875. As a fix for not being able to update Windows 7 on computers that don’t support streaming single instructions multiple data extensions 2, or SSE2, users should upgrade those machines with a processor that does. So Microsoft no longer seems to fix the bug for older PCs, PCWorld notes.
According to the lifecycle overview of Windows 7 with Service Pack 1, this OS should receive support until January 14, 2020, and therefore patches for these kinds of problems. In the original release of March 13 security update KB4088875 for Windows 7, Microsoft first reported the update issues for PCs without SSE2. At that time, the text still stated that a solution was being worked on. Later updates, such as June’s KB4284826, reiterated that claim.
However, this is only apparent from the pages as they appear in the Wayback Machine, because in the current text of the KB4284826 update, Microsoft no longer mentions the SSE2 bug at all and the March one now contains the advice to to upgrade hardware.
Many Pentium IIIs will no longer be in use: Intel introduced the processor in 1999 and the last one was produced in 2003.