If the email time is wrong in Outlook on the web or Outlook.com, correct the mailbox time zone setting first:
- Open Settings.
- Go to Calendar > View.
- Under Time zones, set Display my calendar in time zone to the correct local time zone.
- Select Save.
If needed, also check whether Outlook asks to update the time zone when traveling:
- In the same Calendar > View area, enable When I travel across time zones, ask me if I want to update my time zone.
For Outlook Web App connected to Exchange Server, the time zone is set here:
- Settings > Options > Settings > Regional
- Then select the correct time zone.
If the problem only happens in Outlook on the web and not in Outlook desktop, that matches a known behavior because Outlook desktop uses the Windows client operating system time zone, while Outlook on the web uses its own mailbox/web setting.
In some Exchange environments, incorrect sent times can also happen when the mailbox server is in a region that observes daylight saving time but the user is in a region that does not. In that case, the Exchange Server time zone may also need to be configured to a matching UTC region that does not follow DST.
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