Background: I have a single domain, running in 2 sites that is connected using Site-to-Site VPN.
- Site A is running in time zone 2:00+ UTC
- Site B is running in time zone 4:00+ UTC
DCs are correctly placed into their own corespondent subnet in the Active Directory Sites and Services. All DCs are running Windows 2012 R2, all clients are running Windows 8.1
What I am trying to achieve: sync all users in the domain with an external NTP server for login purposes with an online service, I enabled NTP on the PDC to sync with an external source using the Microsoft FixIT article http://support.microsoft.com/en-us/kb/816042.
What really happened: users in Site A are working correctly, users in Site B are syncing from the PDC too, but their time zone keeps changing from 4:00+ UTC to 2:00+ UTC, users in Site B can change the TZ back to 4:00+ UTC, but whenever their machines resync with the PDC, the TZ changes back to 2:00+ UTC.
How I tried to solve this problem: I created a group policy computer start up script that reads
Tzutil.exe /s "Arabian Standard Time"
The syntax should change the TZ to 4:00 UTC, I linked the login script to Site B, I can confirm that the script is running successfully and the time changes to 2:00+ UTC upon login, however, after awhile, the machines sync to the PDC and the TZ goes back to 2:00+ UTC.
Help?
So I contacted Microsoft for this, they were very puzzled as well, we never figured out why the time zone change by it self or which process was causing this behavior, but they gave me a work around that fixed my problem, I'm going to post here for future referencing (copy/pasting from Microsoft communication with me)
Regarding the current issue, if it is possible, I suggest you define the group policy
to determine which users and groups can change the time zone. Please check my test:
The users which don’t have rights will unable to change the time zone:
Know this is an old issue, however, we were experiencing the same problem at our 2 sites recently so thought we'd share our experience.
There is a Scheduled Task built into Windows called SynchronizeTimeZone that runs tzsync.exe which syncs the Time Zone to the closest RWDC. In our case we disabled this task on clients & used TZUtil.exe to set the correct time zone again.