BleepingComputer reported that Microsoft said on Thursday a set of Windows Update certificates expires on May 17 and June 19, 2027. Devices on Windows versions Microsoft no longer supports will then lose access to Windows Update. Windows 11 25H2 and newer need nothing. Windows 11 24H2 and Windows Server 2025 need the September 2025 security update or later by June 19. Supported Windows 11 and Windows 10 releases, plus Server 2022, need the July 2026 update by that date. Server 2016, Server 2019 and Windows 10 Enterprise 2019 LTSC get an earlier deadline of May 17 for the same July 2026 update.
A certificate is a digital ID that lets systems trust each other. Microsoft calls replacing them standard practice. BleepingComputer says supported systems already hold the new ones. The sources do not say why a listed update must come first. BleepingComputer also says "this" does not apply to devices using WSUS, a tool that spreads updates across company networks. It does not make clear what "this" covers.
For unsupported devices, this is a fixed cut-off, not a slow decline. Budget owners can ask how many such machines they run, which deadline applies to each, and whether upgrades fit before May 2027.