how to edit wrong time zone DST configuration in Exchange Server OWA

Question

starting from March 2023 Daylight Saving Time is no longer applicable in Iran. turning off the "adjust for daylight saving time automatically" button will fix the time issue for Windows and Microsoft Office Outlook, however it seems not to fix the time in Exchange Server OWA and the time there is one hour late. any idea how can this be fixed?

Answer 1

Hi @Saeid Malekhosseini ,

Thanks for your feedback above which shared more information and glad to know that your issue is resolved now! Since our forum has the policy that The question author cannot accept their own answer. They can only accept answers by others, and according to the scenario introduced here: Answering your own questions on Microsoft Q&A

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[how to edit wrong time zone DST configuration in Exchange Server OWA - Summary]*** *

Issue Symptom:*
The time in Exchange Server OWA is one hour late due to Daylight Saving Time is no longer applicable in Iran. *

Solution:*
Edit the Registry Binary values in this registry path: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Time Zones I used tzedit.exe to turn off Daylight Saving Time for the Iran time zone and years 2023 and 2024 to avoid rewriting of TZI binary key.

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Answer 2

Hi @Saeid Malekhosseini ,

You could follow this screenshot, refer to: https://support.microsoft.com/en-us/office/time-zone-and-language-settings-in-outlook-web-app-5565cc28-bc5c-47f1-849d-b57f1ffdfb53

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Answer 3

the solution was to edit the Registry Binary values in this registry path: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Time Zones I used tzedit.exe to turn off Daylight Saving Time for the Iran time zone and years 2023 and 2024 to avoid rewriting of TZI binary key.