Local and Domain NTP Overridden by Secure Time Service

Starting with Windows 10 1511, Microsoft introduced a new feature called Secure Time Seeding, part of the Secure Time Service (STS), as an upgrade to the W32TIME service. The STS uses information from SSL connections to validate NTP data. Information from this feature supersedes all other time sources, including locally configured NTP, domain controllers, and Hyper-V time synchronization.

I first noticed the feature when several of my Hyper-V virtual machines began shifting their system clocks backwards and forwards several times a minute. At first the time changes spanned a few hours, but as the machine uptime climbed, so did the time jumps. Eventually, the time was bouncing backwards and forwards by weeks, several times a minute. The Hyper-V time synchronization service was fighting with the new Secure Time Service and this wrecked havoc on authentication and any other services running on the systems.

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