How are you assigning permissions? How is he opening “the file”? Check the permissions you are assigning. Outlook 2007 has permissions you can assign that Outlook 2003 does not have. Go with the defaults that Outlook 2003 uses. I had this scenario when we were switching from 2003 to 2007 and the 2007 user had granted permissions Outlook 2003 could not recognize and the 2003 user would just get a blank calendar. But he did at least see the calendar. Once we adjusted the permissions granted he could see what was on the calendar as well.