Windows Update Certificates Expire in 2027 and Most PCs Already Have the Replacement
Microsoft will retire the certificates Windows Update uses to prove a PC is talking to a genuine Microsoft update server, on May 17, 2027 and June 19, 2027. The replacements are not a separate download, and most PCs picked them up months ago inside an ordinary security update. Windows 11 version 25H2 and later are the only releases Microsoft lists as needing no action