A fix introduced into Windows last month to close a weakness in Kerberos authentication is causing logon failures for some Windows Hello for Business (WHfB) users, Microsoft has warned.

Some Windows apps use smart cards to allow you to use Windows Hello for Business. However, if your credentials do not comply with smart card apps, you cannot use them to sign in.

Nearly one year after Microsoft launched its flagship Windows 11, the tech giant has officially rolled out its first major update to the operating system.