Strange problem in Outlooks 2007 with Exchange 2007 hosted by Intermedia.net. We have a collection of resource accounts (meeting rooms) with shared calendars that we do bookings against. Some of these calendars refuse to update from cache unless we force an update with Shift+F9. Everything works fine if we turn off Cached Exchage Mode, of course, but operation becomes painfully slow. Deleting and rebuilding the .ost file does not help. Anyone else experiencing this?