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I have two machines and I'd like their clocks to be in sync for various reasons. Machine 1 is an XP machine located in the office. Machine 2 is a VPS hosted by a third party running Windows Server 2008 R2. These machines are not in any kind of workgroup or on a domain together. They are completely separate machines.

Machine 2 is currently syncing once a week to The clock on Machine 2 does seem to wander a bit within that week interval. What I would like to do is have Machine 1 set its clock based on the clock of Machine 2.

I have tried configuring w32tm on the XP machine. This is what I used for configuration:

w32tm /config /syncfromflags:manual /manualpeerlist:"<ip address of machine 2>"

However, whenever I issue the /resync command I get "The computer did not resync because no time data was available". I have made sure to start the windows time service on machine 2, and I have added firewall exceptions for UDP port 123.

Is there something I need to configure on Machine 2 (other than just starting the time service) in order to get it to respond?

Edit: I have also run w32tm /config /reliable:YES /update on Machine 2. I am still getting "The computer did not resync because no time data was available". Is there something else I'm missing?

Edit 2: The solution I used was most closely related to the answer I marked as correct. However, this article offered additional registry tweaks that worked in my case:

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Are either machines a member of any AD domain, even if they're not in the same one? – MDMarra Nov 19 '12 at 19:33
If the clock skews during the week you can set a polling interval (mdmarra has discussed this in the past). Another option would be to set both to use the same 3rd party source. – TheCleaner Nov 19 '12 at 19:40
@MDMarra Unfortunately no - just two independent machines :( – Eric Nov 19 '12 at 21:34
That's actually better for your needs in this case. At least as it related to time services. – MDMarra Nov 19 '12 at 22:07
up vote 2 down vote accepted

Machine 2 needs to be confiugred as an authoritative time source. Ie. NTPSERVER = 1. From the registry key: [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\W32Time\TimeProviders\NtpServer] Enabled = 1

Alternatively you can do that via the command w32tm /config /reliable:YES /update

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I just tried this, and it didn't seem to work. Somewhere along the way I saw some text saying that /reliable:YES was only valid for domain controllers? Unfortunately these machines are not on any domain or workgroup, just standalone machines – Eric Nov 19 '12 at 22:17
I'm marking this as correct, as this was part of the solution. However, I needed to change the AnnounceFlags as well. This url solved my problem:… – Eric Nov 19 '12 at 23:45

There are also some good ports of NTP reference code that I like to use on Windows machines. Look at 
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