In a small three-user environment running Outlook 2007 on Exchange 2010, all users previously just used one user's calendar as their main calendar. New employee #4 has been set up with his own calendar per the owner's request, they use colored categories for their calendar events, and his categorized activities are not showing up as colored on the other users' Outlook calendars - only his own. What settings should I look at to enable the correct color coding again?