How can I set Outlook XP to send iCalendar files along with my invites? If I go to Calendar Options, the "When sending meeting requests over the Internet, use iCalendar format" checkbox is greyed out.

Is it too much to ask? All I want to do is to extract new calendar items from Outlook in iCal format every day at a set time. The reason for this is I am planning to buy a big, new Mac Pro (dual ...