JSI Tip 9916. How does the Windows Time service treat a leap second?

When the Windows Time service, W32Time, is working with the NTP server, it has no method to account for a leap second. It is totally dependent upon the how the NTP server accounts for the leap second.

When the Windows Time service is working as a client, W32Time does NOT indicate the value of the Leap Indicator, causing the computer to be one second faster that the actual time when a leap second occurs. This is resolved at the next time synchronization.

NOTE: See How do I configure the Windows time service to log when time is adjusted?