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What can be the reason to get 2 different results when running

C:\Documents and Settings\wswebuser.OPTI>w32tm /monitor
     OptiDC.opti  *** PDC *** []:
     ICMP: 0ms delay.
     NTP: +0.0000000s offset from OptiDC.opti
       RefID: 'LOCL' []

C:\Documents and Settings\wswebuser.OPTI>w32tm /monitor /computers: []:
    ICMP: 0ms delay.
    NTP: +0.0182962s offset from local clock
        RefID: 'LOCL' []

As you can assume, my PDC is the domain ( I would assume, that the results should have better sync, no?

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There are tons of various parameters that govern the behavior of w32tm:

It's hard to keep up with exactly how often w32tm truly syncs because it seems that they change it in subtle ways with every version of Windows. Regardless, here's a possible answer for how often it syncs:

65532, "SpecialSkew" = once every 45 minutes until 3 good synchronizations occur, then once every 8 hours (3 per day) [default]

65531, "DailySpecialSkew" = once every 45 minutes until 1 good synchronization occurs, then once every day

Every device you have has a built in clock. Each one of these is going to skew over time, in different ways and in differing degrees. They all have their own personality, so to speak.

And if your OS is only synchronizing every 8 hours, there is a lot of time there for a hardware clock to veer off by a few milliseconds.

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