Though I have no way of knowing for sure, I’m thinking some bright young Microsoft Defender Team engineer during a team meeting asked “why are we still updating Defender for non-supported OS’s like XP & Vista” then subsequently some scrupulous mid-level manager received a bonus for submitting a cost savings proposal to upper management and … wallah! … no more Defender updates post 6/11/2018 for non-supported systems to include XP & Vista.
I just did some testing on several of my Windows 7 systems & 1 resurrected Vista system. My results are posted #200783 & #200801.
EDIT:
I think the reason that the “manual” update method still works for Vista is because the engine & definitions are the same (at least as of today) for both Windows 7 & Vista but not sure if it’ll remain that way in the future.
Win7 - PRO & Ultimate, x64 & x86
Win8.1 - PRO, x64 & x86
Groups A, B & ABS
