Ultimately, individual calendar owners are the only ones who can validate that calendars are correct or not. To minimize confusion during the DST shift, follow these simple steps:
1. When organizing a meeting during the extended DST period, type the correct meeting time in the subject line or body of the message (for example, Project planning meeting at 8:30 A.M.).
2. Consider any appointments and meetings in the extended DST period to be suspect. When in doubt, verify the correct time with the organizer.
3. Make a hard copy printout of your Outlook Calendar for the extended DST period.
For more information, visit Microsoft's page regarding 2007 DST changes here
