When you use Exchange server, anyone with proper permission to your calendar can open it and add an appointment. While the person's name or Exchange alias is listed as the Organizer, its not easily discovered by many users. Outlook 2007 makes it easier by placing the organizer's name in the subject field (much to the annoyance of many people).
The easiest way to see who created an item is by adding the From or Organizer field to a table view, such as By Category.
- From the View menu, choose By Category. Look for it under Current view or Arrange by, Current view.
- Right click on the row of field names and choose Field Chooser.
- From the Field Chooser dialog, select All Appointment fields from the dropdown and locate the Organizer field.
- Drag it to the row of field names. Then close the Field Chooser dialog.
Any table view will do or you can make your own custom view if you need to show the Organizer field often.
The From field in All Mail items will also work. It's the exact same field as Organizer.
You can use this method for Tasks, Contacts, and Journal too.