Some certificates required for Windows Update will expire in 2027. Microsoft has told users that devices running unsupported versions of Windows 10 or Windows 11 may lose access to Windows Update starting in May or June 2027.
The certificates authenticate Windows Update servers, letting a computer verify that it’s connected to Microsoft’s official update service to download updates. Windows Update accepts only specific certificates, so a failed authentication prevents the connection. Some required certificates expire on May 17 and June 19, 2027, and Microsoft is distributing replacements through monthly security updates. Devices that don’t install those updates won’t be able to use Windows Update.
Systems running supported Windows versions have already received the replacement certificates, so fully up-to-date systems need no further action. Windows 11 25H2 and later are unaffected because they already have a newer certificate.
Check devices running Windows 11 24H2 or Windows Server 2025, and install the September 2025 security update or a later one by the applicable deadline next year. Microsoft recommends that administrators and users upgrade to a supported Windows version before the certificates expire next year.
After the deadline, packages containing the certificates will still be available, but downloading them will be more cumbersome: users will have to get them manually from Microsoft’s official website.
