Windows Update itself has an expiry date, and it falls in 2027

Every time your PC asks Microsoft for an update, it checks a certificate first to make sure it is talking to the real Windows Update and not something pretending to be it. Those certificates expire, same as the ones behind every padlock in your browser. Two sets of them run out on 17 May and 19 June 2027.

Microsoft published the plan on its Windows IT Pro blog this week, and BleepingComputer picked it up on Thursday. The catch is circular in an uncomfortable way: the new certificates arrive in a Windows update, so a machine that has not installed updates in a long time will not have them, and once the old ones expire it can no longer reach the service that would have supplied them. Microsoft's wording is that affected devices "will stop connecting and receiving all types of updates from Windows Update".

Most people need to do nothing. If you are on Windows 11 25H2 or newer you are already covered. Windows 11 24H2 needs the September 2025 security update or later installed before 19 June 2027. Any other supported Windows 11 release, and Windows 10 on a supported version, needs the July 2026 update or later by the same date. The versions genuinely at risk are the ones that have been left alone for years: an old laptop in a cupboard, a spare PC somebody switched off in 2023 and has not booted since. Those have to be brought up to a supported Windows before the deadline, not after.

Twenty months is plenty of warning, but it only helps if updates are actually going through. If yours have been failing or sitting stuck at a percentage for weeks, Tendvane's Windows Update repair wizard is the thing to try first.