There appears to be a lot of conflicting information about configuring Windows time on a virtualised Windows 2008 server. Some of this will stem from the variety of hypervisors in use.

In this case the Windows 2008 server is running under Hyper-V and it appears to be hitting the hardware clock of the host system on every restart.

So depending on what you read you will find advise to manage via the Hyper-V management in the host (which sometimes is not accessible in hosted environments) or to just turn off the Hyper-V sync (depending on which of the posts you believe on that page) and work on the NTP settings.

For this VPS I don’t have access to the Hyper-V and don’t know what the settings are.

In summary I have modified the w32time setting to use an external ntp server at the command prompt rather than relying on the graphical interface that reported the correct settings but running a w32tm query suggested different settings existed.

From a command prompt:

[text]

w32tm /query /status # this just confirmed that the server was not using the ntp server that was set in the graphical interface

w32tm /config /syncfromflags:manual /manualpeerlist:0.pool.ntp.org

w32tm /query /status # confirm changes

[/text]

and with Regedit (this is possibly redundant but I’d prefer to see more frequent checks for NTP than 24 hours and 15 minutes seems ok. Could easily be an hour using 3600 as the setting.)

[text]

HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServicesW32TimeTimeProvidersNtpClient (SpecialPollInterval)    and modified Decimal value to 900 (15 minutes)

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And after 2 restarts this morning it all appears to have resolved correctly and the correct time zone hours are still being displayed.

References for results:

Managing the NTP settings under Windows 2008 provided the basic commands and I also read this but the syntax for 3 sources did not work (I did not try to work out why as I am ok with one NTP server selected).

This page provided the regedit info that I needed to get the NTP working every 15 minutes rather than 7 days apart.

This blog post over at Apeture was a funny read and includes some more registry info which helped to clarify the NTP settings.