What are possible reasons why a calendar entry in OWA is at a different time than in Outlook?

Question

We have two Exchange 2003 servers, our primary server and a front-end server that hosts Outlook Web Access (OWA). When I open my boss' calendar via Outlook 2007 (from my Outlook client as well as hers) I see the event scheduled for 10:30 am. When I open her calendar via Outlook Web Access, the same event is scheduled for 4:30 am.

I don't understand Exchange well-enough to imagine how this is possible. If you have any ideas why this could be happening, I greatly appreciate it. I'd also very much appreciate any insight you have to how this could be possible. There must be some cached data on the front-end server that causes the calendar entry to appear at a different time, I suppose. Any insight into how Exchange manages that cache and where I could look for an issue would be very helpful.

Thank you!

Solution 1

This is almost certainly a time zone issue in OWA.

Outlook adopts the time zone of the host operating system; both of your client machines are configured for the same time zone, so the appointment is displayed at the same time on both machines in Outlook.

Outlook Web Access can't make the assumption that the client machine where the web browser is running is in the same time zone as the server, so the Outlook Web Access client provides a user-configurable option where the user can set their current time zone. This information is stored for each user.

Sign in to Outlook Web Access, navigate to the Options page and select the Date & Time Formats section to check the current time zone setting. Select the correct time zone and click the Save button and you should be able to avoid showing up to meetings four hours early!

Note that these options in Outlook Web Access are stored per-user, so the user experiencing the problem will need to check and modify this setting.

We currently use Exchange 2007; Outlook Web Access for Exchange 2007 calls this Options section "Regional Settings" instead of "Date & Time Formats" but it works the same.

I believe that users are prompted to configure their time zone the very first time they sign in to Outlook Web Access; however, most users of Outlook Web Access aren't aware of this setting, so if is set incorrectly or needs to be changed, most people don't even know to look for it...

Solution 2

In my experience it is usually a timezone issue. The calendar items are stored with UTC time and the the display is calculated based on the timezone you are viewing it in. Are the servers stored in a different timezone then the client? I believe there is an option to control whether or not the displayed time is locked to your timezone when you create the calendar item but I don't have access to Outlook right now to confirm.

EDIT:
The screen shot below is from outlook 2003, you are able to specify which timezone the meeting takes place in.

Here is a hypothetical scenario to better explain how this could happen:
You live on the east coast and create an appointment in outlook to take place at 3pm on the east coast. Because you computers timezone is EST then it will set the appointment to be EST. Your servers though are in a CoLo facility on the west coast that was setup in PST. So when you log into OWA to view your calendar it is viewing it in PST and translating the time of the appointment to be 12pm instead of 3pm.

I've seen this happen more frequently though with mobile phones that change their timezone automatically when traveling and so when you create the meeting it creates it in whatever timezone you happen to be in. This is beneficial but confusing if your desktop or server is in a different timezone.

Comments

[Ken Pespisa]

Note that 99% of her calendar entries are fine. There is just this one recurring entry that is off, and only off in Outlook Web Access. For the other user who was invited to this meeting (in the same office, same server) the item appears at the correct time in both OWA and Outlook.

[einstiien]

Please see my update